Piperazine derivatives

ABSTRACT

Novel 1-substituted 4-(diarylmethyl)piperazine derivatives having antianaphylactic and antihistaminic properties.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of our copending application Ser. No.088,703, filed Oct. 26, 1979, now abandoned, which in turn is a divisionof application Ser. No. 375,342, filed Feb. 6, 1978, now U.S. Pat. No.4,200,641, which in turn is a continuation of application Ser. No.753,062, filed Dec. 21, 1976, now abandoned, which in turn is acontinuation-in-part of application Ser. No. 672,919, filed Apr. 2,1976, now abandoned.

BACKGROUND OF THE INVENTION

In the prior art there may be found a number of1-[(heterocyclyl)alkyl]piperazines and a number of 1-substituted4-(diarylmethyl)piperazine and 4-(diarylmethoxy)piperidine derivativeshaving pharmacological properties. Such compounds are described in thefollowing references:

U.S. Pat. No. 3,362,956;

U.S. Pat. No. 3,472,854;

U.S. Pat. No. 3,369,022;

U.S. Pat. No. 2,882,271;

U.S. Pat. No. 3,956,328; and

C.A., 64, 3499e (1966).

The compounds of this invention differ from the foregoing essentially bythe nature of the B--C_(n) H_(2n) -group, present in the 1-position ofthe piperazine or piperidine group, and/or by the nature of thediarylmethyl or diarylmethoxy group present in the 4-position of saidpiperazine, respectively piperidine group.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

This invention relates to novel chemical compounds and more particularlyto piperazine and piperidine derivatives which may structurally berepresented by the formula: ##STR1## and the pharmaceutically acceptableacid addition salts thereof, wherein: Ar¹ and Ar² are each independentlyselected from the group consisting of phenyl, substituted phenyl andpyridinyl, wherein said substituted phenyl is phenyl having from 1 to 2substituents independently selected from the group consisting of halo,lower alkyl, lower alkyloxy, trifluoromethyl and nitro;

m is the integer zero or 1;

A is a member selected from the group consisting of ##STR2## providedthat when said A is ##STR3## then said m is zero and when said A is##STR4## then said m is 1; n is an integer of from 2 to 6 inclusive,provided that when C_(n) H_(2n) represents a branched alkylene chain,then at least 2 carbon atoms are present in the linear portion of thechain linking B with the piperidine or piperazine nitrogen atom; and

B is a member selected from the group consisting of:

(a) a radical having the formula ##STR5## wherein: R¹ and R² are eachindependently selected from the group consisting of hydrogen, halo,lower alkyl and trifluoromethyl; and

Y is a member selected from the group consisting of oxygen, sulfur and asubstituted nitrogen of the formula ##STR6## wherein said L is a memberselected from the group consisting of hydrogen, lower alkyl, loweralkylcarbonyl, lower alkyloxycarbonyl-lower alkyl, carboxy-lower alkyl,phenyl, phenylmethyl, lower alkylaminocarbonyl, hydroxymethyl, and loweralkenyl; and

(b) a radical having the formula ##STR7## wherein: R¹ and R² are eachindependently selected from the group consisting of hydrogen, halo,lower alkyl, and trifluoromethyl; and

M is a member selected from the group consisting of hydrogen, loweralkyl, phenyl, phenylmethyl, mercapto, lower alkylthio, amino, loweralkylcarbonylamino, lower alkyloxycarbonylamino, and cycloalkyl havingfrom 3 to 6 carbon atoms.

As used in the foregoing and in the following definitions, "lower alkyl"is meant to include straight and branch chained hydrocarbon radicalshaving from 1 to 6 carbon atoms such as, for example, methyl, ethyl,1-methylethyl, 1,1-dimethylethyl, propyl, butyl, pentyl, hexyl and thelike; "lower alkenyl" is meant to include straigth and branch chainedalkenyl radicals having from 2 to 6 carbon atoms such as, for example,ethenyl, 1-methylethenyl, 1-propenyl, 2-propenyl, 2-butenyl,1-methyl-2-butenyl, 2-pentenyl, 2-hexenyl and the like; "cycloalkyl"refers to cyclic hydrocarbon radicals having from 3 to 6 carbon atomssuch as, for example, cyclopropyl, cyclobutyl, cyclopentyl andcyclohexyl; the expression "C_(n) H_(2n) " refers to straight and branchchained alkylene chains having from 2 to 6 carbon atoms and having atleast 2 carbon atoms in the linear portion of the chain linking theB-group with the piperidine or piperazine nitrogen, such as, forexample, 1,2-ethanediyl, 1,3-propanediyl, 2-methyl-1,3-propanediyl,1,4-butanediyl, 2-methyl-1,4-butanediyl, 1,5-pentanediyl, 1,6-hexanediyland the like; and the term "halo" is generic to halogens of atomicweight less than 127, i.e., fluoro, chloro, bromo and iodo.

The subject compounds of formula (I), except those wherein B stands fora 2-amino-1H-benzimidazol-1-yl radical, may conveniently be prepared byreacting an appropriate reactive ester of formula (II) wherein n is aspreviously defined, B is as previously defined except a2-amino-1H-benzimidazol-1-yl radical of the formula ##STR8## wherein R¹and R² are as previously defined, and W is an appropriate reactive esterfunction derived from the corresponding alcohol such as, for example,halo, methanesulfonyl, 4-methylbenzenesulfonyl and the like, with anappropriate piperidine or piperazine derivative of formula (III) whereinA, m, Ar¹ and Ar² are as previously defined: ##STR9##

The foregoing condensation reaction is preferably carried out in anappropriate reaction-inert organic solvent such as, for example, a loweralkanol, e.g. methanol, ethanol, propanol, butanol and the likealkanols; an aromatic hydrocarbon, e.g., benzene, methylbenzene,dimethylbenzene and the like; an ether, e.g., 1,4-dioxane,1,1'-oxybispropane and the like; a ketone, e.g., 4-methyl-2-pentanone;N,N-dimethylformamide; nitrobenzene; and the like. The addition of anappropriate base such as, for example, an alkali metal or earth alkalimetal carbonate or hydrogen carbonate, may be utilized to pick up theacid which is liberated during the course of the reaction. A smallamount of an appropriate metal iodide, e.g., sodium or potassium iodidemay be added as a reaction promotor. Somewhat elevated temperatures areappropriate to enhance the rate of the reaction and preferably thereaction is carried out at the reflux temperature of the reactionmixture.

In this and following preparations, the reaction products are separatedfrom the reaction mixture and, if necessary, further purified by theapplication of methodologies generally known in the art.

The compounds of formula (I) wherein B stands for a2-amino-1H-benzimidazol-1-yl radical, (I-a), are easily preparedstarting from the corresponding compounds (I) wherein B stands for a2-(lower alkyloxycarbonylamino)-1H-benzimidazol-1-yl radical, (I-b), bydecarboxylating the latter under hydrolytic conditions, for example, byacid hydrolysis using an appropriate strong acid, such as hydrochloric,hydrobromic or sulfuric acid, or by alkaline hydrolysis using anappropriate strong base such as, for example, sodium or potassiumhydroxide. ##STR10##

It is to be noted that when the B-group in compounds of formula (I) orin intermediates therefor stands for a 2-(loweralkyloxycarbonylamino)-1H-benzimidazol-1-yl or a 2-(loweralkylcarbonylamino)-1H-benzimidazol-1-yl radical, then said radicals mayexist in different tautomeric forms as is illustrated hereafter:##STR11## Such tautomeric forms of compounds of formula (I) arenaturally intended to be within the scope of this invention.

Compounds of formula (I) which may be represented by the formula (I-c):##STR12## wherein R¹, R², n, A, Ar¹ and Ar² are as previously definedmay alternatively be prepared by ring closure of an appropriateintermediate of formula (IV) with an appropriate cyclizing agent asknown in the art for the preparation of1,3-dihydro-2H-benzimidazol-2-ones starting from 1,2-benzenediamines.

Suitable cyclizing agents which may advantageously be employed include,for example, urea, carbonyl dichloride and alkali metal isocyanates, andthe cyclization reaction may be performed following methodologiesgenerally known in the art. For example, when urea is used as thecyclizing agent the compounds (I-c) are easily obtained by stirring andheating the reactants together in the absence of any solvent.

The foregoing preparations may be illustrated as follows. ##STR13##

The compounds of formula (I-c) may still be prepared starting from thecorresponding compounds of formula (V) ##STR14## wherein R¹, R², n, A,m, Ar¹ and Ar² are as previously defined and P is an appropriateprotecting group, by the removal of said protecting group according toconventional procedures. As examples of such protecting groups there maybe mentioned lower alkyloxycarbonyl and, a substituted ethenyl group ofthe formula ##STR15## wherein R³ and R⁴ may represent different groupsbut wherein R³ is preferably lower alkyl and R⁴ is preferably hydrogen,lower alkyl or phenyl.

When the protecting group is lower alkyloxycarbonyl, it may easily beremoved by alkaline hydrolysis, and when the protecting group is asubstituted ethenyl group it is conveniently eliminated by subjectingthe appropriate intermediate (V) to acid hydrolysis. In carrying out theacid hydrolysis to remove the substituted ethenyl group from (V) a widevariety of protonic acids may be employed, including mineral acids suchas, for example, hydrochloric, hydrobromic, sulfuric, nitric andphosphoric acid, and organic acids such as, for example, acetic,propanoic, ethanedioic and the like acids. Further the reaction may becarried out in reaction-inert organic solvents as commonly employed insuch a type of hydrolytic reactions, e.g., lower alkanols such as, forexample, methanol, ethanol, 2-propanol and the like.

In a procedure similar to that described for the preparation of thecompounds (I-c) starting from (IV) there may also be prepared compoundsof the formula (I-d) ##STR16## wherein R¹, R², n, A, m, Ar¹ and Ar² areas previously defined, and M¹ is selected from the group consisting ofhydrogen, lower alkyl, phenyl, phenylmethyl, mercapto, amino, loweralkyloxycarbonylamino and cycloalkyl, by the reaction of (IV) with anappropriate cyclizing agent, following art-known methodologies ofpreparing 1H-benzimidazoles starting from 1,2-benzenediamines. Dependingon the nature of M¹ in the compounds (I-d) the following cyclizingagents may, for example, be employed.

When M¹ stands for hydrogen there may be used formic acid or anappropriate tri(alkyloxy)methane as a cyclizing agent.

When M¹ stands for lower alkyl, phenyl, phenylmethyl or cycloalkyl, onemay use a carboxylic acid of the formula

    R.sup.5 --COOH                                             (VI)

wherein R⁵ is lower alkyl, phenyl, phenylmethyl, or cycloalkyl, or afunctional derivative thereof such as, for example, an acyl halide, anester, an amide or a nitrile derived from such acid or an iminoester ofthe formule ##STR17## wherein R⁵ is as defined hereabove; or an aldehydeof the formula ##STR18## or an addition product thereof with an alkalimetal hydrogen sulfite. When the cyclizing agent is an aldehyde theremay be added to the reaction mixture an appropriate oxidizing agent suchas, for example, nitrobenzene, mercuric oxide, Cu(II) and Pb (II) saltsor other suitable oxidants as known in the art, or the aldehyde itself,when added in excess, may serve as an oxidant.

When M¹ stands for mercapto there may be used cyclizing agents such as,for example, carbon disulfide, thiourea, carbonothioic dichloride,ammonium thiocyanate and the like.

When M¹ is an amino group, ring closure may be performed with cyanamide,or a metal salt thereof, preferably an alkali or earth alkali metalsalt, or with BrCN.

When M¹ stands for lower alkyloxycarbonylamino, one may use as acyclizing agent, for example, an appropriate lower alkyl(iminomethoxymethyl)carbamate of the formula (IX) ##STR19## a loweralkyl [(lower alkoxycarbonylamino)(R⁶ -thio)methylene]carbamate of theformula (X) ##STR20## wherein R⁶ is hydrogen or methyl; or a lower alkylcarbonoisothiocyanatidate of the formula (XI) ##STR21## a lower alkyllower alkylcarbamothioate of the formula (XII) ##STR22## a dilower alkylcyanimidodicarbonate of the formula (XIII) ##STR23##

The foregoing cyclization reactions may all be performed followingwell-known methodologies as described in the literature.

Compounds of the formula (I-e) ##STR24## may alternatively be preparedby the acylation of an appropriate 2-amino-1H-benzimidazol-1-ylderivative of formula (I-a) following standard N-acylating procedures,e.g., by the reaction of (I-a) with an appropriate lower alkylcarbonylhalide or with an anhydride derived from a lower alkylcarboxylic acid.

Compounds of the formula (I-f) ##STR25## wherein R¹, R², n, A, m, Ar¹and Ar² are as previously defined and L¹ is selected from the groupconsisting of lower alkyl, lower alkylcarbonyl, loweralkyloxycarbonyl-lower alkyl, carboxy-lower alkyl, phenylmethyl, loweralkylaminocarbonyl, hydroxymethyl and lower alkenyl, provided that theunsaturation in said lower alkenyl is located in a position other thanα, may still be prepared by the introduction of said L¹ into a compoundof formula (I-c) ##STR26##

Depending on the nature of the L¹ group to be introduced the followingmethods may be utilized therefor.

When L¹ stands for lower alkyl, lower alkyloxycarbonyl-lower alkyl,phenylmethyl or lower alkenyl, in which case the symbol L¹ _(a) is usedtherefor, the introduction of said L¹ _(a) into (I-c) may be performedby the reaction of (I-c) with an appropriate reactive ester of theformula L¹ _(a) -W, (XIV), wherein L¹ _(a) is as defined hereabove and Whas the same meaning as assigned to it in the definition of the startingmaterials of formula (II).

The condensation of (XIV) with (I-c) may be carried out under similarconditions as described hereinbefore for the condensation of thereactive esters (II) with the intermediates of formula (III). In orderto enhance the reaction rate it may be appropriate in some instances toadd to the reaction mixture a small amount of an appropriate macrocyclicpolyether such as, for example,2,3,11,12-dibenzo-1,4,7,10,13,16-hexaoxacyclooctadeca-2,11-diene as areaction promotor.

When the L¹ group to be introduced is lower alkyloxycarbonylethyl, theintroduction of said group may alternatively be performed by reacting(I-c) with a (lower alkyl) 2-propenoate of formula (XV)

    (lower alkyl)OOC--CH═CH.sub.2                          (XV).

Said reaction may conveniently be carried out in a reaction-inertorganic solvent such as, for example, an aromatic hydrocarbon, e.g.,benzene, methylbenzene, dimethylbenzene and the like; an ether, e.g.,1,1'-oxybisethane, 2,2'-oxybispropane, tetrahydrofuran, 1,4-dioxane andthe like, preferably in the presence of an appropriate aminium hydroxidesuch as, for example, N,N,N-triethylbenzenemethanaminium hydroxide.

Compounds of formula (I-f) wherein L¹ stands for carboxy-lower alkyl caneasily be derived from the corresponding lower alkyloxycarbonyl-loweralkyl substituted compunds by hydrolyzing the latter in the usualmanner, e.g., with aqueous alkali, to liberate the acid from the ester.

When the L¹ group is lower alkylcarbonyl said group may conveniently beintroduced by the reaction of (I-c) with an appropriate acylating agentderived from the corresponding lower alkylcarboxylic acid such as, forexample, a halide, preferably the chloride, or an anhydride, followingstandard N-acylating procedures.

When L¹ stands for lower alkylaminocarbonyl it may be introduced by thereaction of (I-c) with an appropriate isocyanatoalkane in an appropriatereaction-inert organic solvent such as, for example, an ether, e.g.,1,1'-oxybisethane, 2,2'-oxybispropane, 1,4-dioxane and the like.

When L¹ is a hydroxymethyl group its introduction is convenientlyperformed by the reaction of (I-c) with formaldehyde in an appropriateorganic solvent such as, for example, N,N-dimethylformamide.

Compounds of the formula (I-g) ##STR27## wherein B, n, Ar¹ and Ar² areas previously defined may alternatively be prepared by the condensationof a piperazine derivative of formula (XVI) with an appropriate reactiveester of formula (XVII) wherein Ar¹, Ar² and W are as previouslydefined, under similar conditions as described hereinbefore for thepreparation of the compounds (I) starting from (II) and (III). ##STR28##

Compounds of the formula (I-h) ##STR29## are also conveniently preparedstarting from the corresponding -SH substituted analogs by standardS-alkylating procedures, e.g., by the reaction of the mercapto compoundwith an appropriate halo-lower alkane in an appropriate organic solventsuch as, for example, a lower alkanol, e.g., ethanol, propanol,2-propanol, butanol and the like.

A number of the intermediates of formula (II) are known compounds andsome of them are described in U.S. Pat. Appln. Ser. No. 597,793, filedJuly 21, 1975 and in U.S. Pat. Appln. Ser. No. 620,727, filed Oct. 8,1975, and they may all be prepared following methodologies which areknown per se. Depending on the nature of B in said intermediates (II)the following procedures may be utilized for preparing them.

Intermediates of the formula (II-a) ##STR30## may be prepared asfollows:

An appropriately substituted 2-chloronitrobenzene of formula (XVIII) isreacted with an appropriate aminoalkanol (XIX) by refluxing thereactants together in an appropriate reaction-inert organic solvent suchas, for example, a lower alkanol, e.g., ethanol, propanol, 2-propanol,butanol and the like, whereupon a [(2-nitrophenyl)amino]alkanol offormula (XX) is obtained, which in turn is subjected to a nitro-to-aminereduction, e.g., by catalytic hydrogenation using Raney-nickel catalyst.The thus obtained intermediate (XXI) is then reacted with an appropriatecyclizing agent as described hereinbefore for the preparation of thecompounds (I-c) starting from (IV), and the thus obtained alcohol offormula (XXII) is subsequently converted into the desired reactive ester(II-a) by the application of methodologies known in the art. Halides areconveniently prepared by the reaction of (XXII) with an appropriatehalogenating agent such as, for example, sulfinyl chloride, sulfurylchloride, phosphor pentachloride, phosphor pentabromide, phosphorylchloride and the like. When the reactive ester is an iodide, it ispreferably derived from the corresponding chloride or bromide by thereplacement of that halogen with iodine. Other reactive esters such asmethanesulfonates and 4-methylbenzenesulfonates are obtained by thereaction of the alcohol with an appropriate sulfonyl halide such as, forexample, methanesulfonyl chloride and 4-methylbenzenesulfonyl chloriderespectively.

The foregoing reactions are more clearly illustrated in the followingschematic representation. ##STR31##

Alternatively the intermediates of formula (II-a) may also be preparedby:

(i) reacting a compound of formula (XXIII) wherein R³ and R⁴ are aspreviously defined with a haloalkanol of formula (XXIV) by conventionalN-alkylating procedures to obtain an alcohol of formula (XXV);

(ii) converting the hydroxyl function of (XXV) into a reactive estergroup in the usual manner as previously described; and

(iii) eliminating the substituted ethenyl group of the thus obtained(XXVI) by acid hydrolysis as described hereinbefore for the preparationof (I-c) starting from (V).

The introduction of the hydroxyalkyl chain in (XXIII) to obtain (XXIV)may also be performed by the reaction of (XXIII) with an appropriate2-(haloalkyloxy)tetrahydro-2H-pyran of formula (XXVII), yielding anintermediate of formula (XXVIII), the ether function of which ishydrolytically split open, e.g., by the treatment with an aqueoushydrochloric acid solution.

When the reactive ester (II-a) is a halide, (II-a-1), it mayalternatively be prepared by the reaction of (XXIII) with an equivalentamount of an appropriate dihaloalkane, (XXIX) in the presence of anappropriate strong base such as, for example, sodium methoxide, orfollowing a Mackosza procedure using aqueous alkali and a quaternaryammonium catalyst, e.g., N,N,N-triethylbenzenemethanaminium chloride,yielding an intermediate of formula (XXVI-a), the substituted ethenylgroup of which is subsequently removed by acid hydrolysis, to yield thedesired halide (II-a-1).

It is to be noted that the same procedures are also applicable when thesubstituted ethenyl group is replaced by another appropriate protectinggroup, except that removal thereof has to be performed followingappropriate methods for the elimination of the particular groupinvolved.

The foregoing reactions are more clearly illustrated in the followingschematic representation. ##STR32##

Intermediates of the formula (II-b) ##STR33## wherein R¹, R², n and Ware as previously defined and L² is selected from the group consistingof lower alkyl, lower alkenyl, lower alkyloxycarbonyl-lower alkyl,phenyl, phenylmethyl and lower alkylaminocarbonyl, may conveniently beprepared by the introduction of the reactive ester side chain into astarting material of the formula (XXX) ##STR34## following similarprocedures to those described hereinbefore for the preparation of theintermediates (XXVI) starting from (XXIII).

Intermediates of the formula (II-c) ##STR35## may be prepared startingfrom the corresponding (II-a) by hydroxymethylation of the latter in theusual manner with formaldehyde.

Intermediates of the formula (II-d) ##STR36## except those wherein Mstands for a mercapto or lower alkylthio group, are convenientlyobtained by the introduction of the reactive ester side chain into astarting material of the formula (XXXI) ##STR37##

The introduction of the C_(n) H_(2n) -W group may be performed followingsimilar procedures to those described hereinbefore for the introductionof said group into starting materials of formula (XXIII). Intermediatesof formula (II-e) ##STR38## wherein R¹, R², M¹, n and W are aspreviously defined, may be prepared by subjecting an appropriate alcoholof formula (XXI) to ring closure with an appropriate cyclizing agent asdescribed hereinbefore, followed by the conversion of the hydroxyl groupof the thus obtained intermediate of formula (XXXII) into a reactiveester group. ##STR39##

The intermediates of the formula (II-f) ##STR40## are convenientlyobtained by S-alkylation of an appropriate intermediate of formula(XXXII), wherein M¹ stands for mercapto (XXXII-a), following standardS-alkylating procedures, e.g. with an appropriate halolower alkane andsubsequent conversion of the hydroxyl function of the thus obtained(XXXIII) into a reactive ester group. ##STR41##

Intermediates of the formula (II-g) ##STR42## are conveniently preparedby N-acylation of the corresponding amino substituted analog, (II-h),##STR43## following procedures known to those skilled in the art, e.g.,by the reaction of (II-h) with an appropriate lower alkylcarbonyl halideor with an anhydride derived from an appropriate lower alkylcarboxylicacid.

The intermediates of formula (IV) are obtained by the condensation of anappropriate reactive ester of formula (XXXIV) with a piperazine orpiperidine derivative of formula (III) followed by the reduction of thenitro group of the thus obtained intermediate (XXXV) to an amino groupaccording to standard nitro-to-amine reduction procedures, e.g., by thereaction of the nitro compound with nascent hydrogen or by catalytichydrogenation in the presence of an appropriate catalyst such as, forexample, Raney-nickel. ##STR44## The reactive esters of formula (XXXIV),used as starting materials herein are easily prepared from an alcohol offormula (XX) by the conversion of the hydroxyl function thereof into areactive ester group following standard procedures as previouslydescribed herein.

The intermediates of formula (V) may be obtained by the condensation ofa reactive ester of formula (XXXVI) with a piperazine or piperidinederivative of formula (III) ##STR45## The reactive ester (XXXVI) used asa starting material herein is in turn prepared by introducing the C_(n)H_(2n) W group into a starting material of formula (XXXVII) ##STR46##following the procedures described hereinbefore.

The intermediates of formula (XVI) may be prepared by the reaction of areactive of formula (II) with a piperazine derivative of formula(XXXVIII) wherein Q is an appropriate protecting group such as, forexample, phenylmethyl or lower alkyloxycarbonyl, and subsequentlyeliminating said protecting group Q from the thus obtained intermediate(XXXIX) following standard procedures as known in the art, for example,by catalytic hydrogenation using palladium-on-charcoal catalyst when Qstands for phenylmethyl, or by alkaline hydrolysis when Q stands forlower alkyloxycarbonyl. ##STR47##

Intermediates of formula (XVI-a) ##STR48## may alternatively be preparedby the reaction of (XXXVI) with (XXXVIII) to obtain an intermediate offormula (XL) and subsequently eliminating the protecting groups P and Qby appropriate procedures as generally known in the art. ##STR49##

Intermediates of formula (III) wherein A is ##STR50## and m is 0,(III-a), are generally known and they may all be prepared by theapplication of methodologies known in the art. Such intermediates(III-a) may for example, be prepared by first subjecting an appropriatearoyl halide to a Friedel-Crafts reaction with an appropriate arene toobtain an Ar¹, Ar² -methanone which in turn is reduced in the usualmanner, e.g., with sodium borohydride to the corresponding methanol. Thelatter is then converted into a reactive ester (XVII) following standardprocedures of preparing reactive esters starting from alcohols and thedesired intermediates (III-a) are subsequently obtained by the reactionof (XVII) with piperazine.

The intermediates of formula (III) wherein A is ##STR51## and m is 1,(III-b), may conveniently be prepared by O-alkylation of a 4-piperidinolof formula (XLI) wherein Q is an appropriate protecting group aspreviously defined with an appropriate reactive ester of formula (XVII),followed by the removal of the protecting group of the thus obtained(XLII) in the usual manner. ##STR52##

The primary starting materials used in all of the foregoing preparationsare generally known and they may all be prepared following methodologiesknown to those skilled in the art.

The compounds of formula (I) may be converted to the therapeuticallyactive non-toxic acid addition salt form by treatment with anappropriate acid, such as, for example, an inorganic acid, such ashydrohalic acid, e.g., hydrochloric, hydrobromic, and the like, andsulfuric acid, nitric acid, phosphoric acid and the like; or an organicacid, such as, for example, acetic, propanoic, hydroxyacetic,2-hydroxypropanoic, 2-oxopropanoic, propanedioic, butanedioic,(Z)-2-butenedioic, (E)-2-butenedioic, 2-hydroxybutanedioic,2,3-dihydroxybutanedioic, 2-hydroxy-1,2,3-propanetricarboxylic, benzoic,3-phenyl-2-propenoic, α-hydroxybenzeneacetic, methanesulfonic,ethanesulfonic, benzenesulfonic, 4-methylbenzenesulfonic,cyclohexanesulfamic, 2-hydroxybenzoic, 4-amino-2-hydroxybenzoic and thelike acids. Conversely, the salt form can be converted by treatment withalkali into the free base form.

The subject compounds of formula (I) and the pharmaceutically acceptableacid addition salts thereof possess strong anti-anaphylactic andantihistaminic properties and as such they are useful agents in humanand animal therapy. The useful anti-anaphylactic and antihistaminicproperties of the compounds of this invention are clearly demonstratedby the results obtained in the test procedures described hereafter.

It is emphasized that the compounds listed in the accompanying tablesare not given for the purpose of limiting the invention thereto, butonly to exemplify the useful anti-anaphylactic and antihistaminicproperties of all the compounds within the scope of formula (I).

A. Materials and methods (a) Anti-anaphylactic and antihistaminiceffects in "vivo"

The anti-anaphylactic and antihistaminic effects of the subjectcompounds (I) and salts thereof are studied "in vivo" in guinea pigs.

Guinea pigs, weighing between 400 and 500 g, are sensitized to ovalbuminby subplantar (s.p.) injection of 0.05 ml of antiserum in the left hindpaw. The animals are then starved and orally treated, 24 hours after thesensitization, with saline (=control animals) or a particular dose ofthe compound under investigation.

The histamine injection (at a dose of 50 μg) was given s.p. in the righthind paw 2 hours after the oral pretreatment with the compound. Thediameters of both hind paws are first measured before the histamineinjection is given and again 10 minutes thereafter. The animals arechallenged intravenously with 0.6 mg of ovalbumin 30 minutes after thehistamine injection. All control animals develop tyical primaryanaphylactic shock symptoms (coughing, difficult breathing, convulsions)and 85% of these control animals die within 15 minutes after theovalbumin injection. Protection against death is used as the criterionfor possible drug effects and the estimated ED₅₀ -value, i.e. the oraldose whereby the protection is observed in 50% of the guinea pigs, islisted in the tables below.

The median histamine paw oe dema in 200 control animals 10 minutes afterthe histamine injection is 15 units (1 unit=0.1 mm). Reactions below 10units, occuring in less than 5% of the control animals are defined aseffective inhibition of histamine oe dema in the compound-treatedanimals and the oral dose-levels whereby this effective inhibition isseen, is also listed in the following tables.

(b) Anti-histamine activity in "vitro"

Guinea-pig ileum strips are suspended in a 100 ml Tyrode bath at 37.5°C. with a preload of 0.75 g and gassed with 95% O₂ and 5% CO₂.

The histamine-(0.5 mg/liter) induced spasms are recorded Kymographicallywith an isotonic lever giving a 5-fold magnification. The interaction ofthe compound to be tested (5 minutes incubation time) with the agonistis studied and the tables below give the effective concentration (inmg/l) of the different compounds whereby a significant inhibition (50%)of the histamine-induced contraction is measured.

As a result of the foregoing tests, the subject compounds (I) andpharmaceutically acceptable salts thereof are generally found active asanti-allergic agents in doses ranging from about 0.25 to about 20 mg/kgbody weight upon systemic administration to warm-blooded animals.

In view of their useful antihistaminic and anti-anaphylactic activity,the subject compounds may be formulated into various pharmaceuticalforms for administration purposes. To prepare the pharmaceuticalcompositions of this invention, an effective antihistaminic oranti-anaphylactic amount of the particular compound, in base oracid-addition salt form, as the active ingredient is combined inintimate admixture with a pharmaceutically acceptable carrier, whichcarrier may take a wide variety of forms depending on the form ofpreparation desired for administration.

These pharmaceutical compositions are desirable in unitary dosage formsuitable, preferably, for administration orally, rectally or byparenteral injection. For example, in preparing the compositions in oraldosage form, any of the usual pharmaceutical media may be employed, suchas, for example, water, glycols, oils, alcohols and the like in the caseof oral liquid preparations such as suspensions, syrups, elixirs andsolutions; or solid carriers such as starches, sugars, kaolin,lubricants, binders, disintegrating agents and the like in the case ofpowders, pills, capsules and tablets. Because of their ease inadministration, tablets and capsules represent the most advantageousoral dosage unit form, in which case solid pharmaceutical carriers areobviously employed. For parenteral compositions, the carrier willusually comprise sterile water, at least in large part, though otheringredients, for example, to aid solubility, may be included. Injectablesolutions, for example may be prepared in which the carrier comprisessaline solution, glucose solution or a mixture of saline and glucosesolution. Injectable suspensions may also be prepared in which caseappropriate liquid carriers, suspending agents and the like may beemployed. Acid addition salts of (I), due to their increased watersolubility over the corresponding base form, are obviously more suitablein the preparation of aqueous compositions.

It is especially advantageous to formulate the aforementionedpharmaceutical compositions in dosage unit form for ease ofadministration and uniformity of dosage. Dosage unit form as used in thespecification and claims herein refers to physically discrete unitssuitable as unitary dosages, each unit containing a predeterminedquantity of active ingredient calculated to produce the desiredtherapeutic effect in association with the required pharmaceuticalcarrier. Examples of such dosage unit forms are tablets (includingscored or coated tablets), capsules, pills, powder packets, wafers,injectable solutions or suspensions, teaspoonfuls, tablespoonfuls andthe like; and segregated multiples thereof.

                                      TABLE I-a                                   __________________________________________________________________________     ##STR53##                                                                                                                      Anaphylaxis                                                           Histamine in                                                                          in guinea pigs oral                                             Base or                                                                             "vitro" (ileum)                                                                        effective dose in                                                            mg/kg                                                           Salt  effective conc.                                                                       Sur-                        L         R.sup.1                                                                           R.sup.2                                                                           C.sub.n H.sub.2n                                                                         R.sup.6                                                                          R.sup.7                                                                           form  in mg/l vival                                                                             Histamine               __________________________________________________________________________                                                          oedema                  H         H   H   (CH.sub.2).sub.2                                                                         H  H   base  0.01    0.63                                                                              1.25                    H         5-Cl                                                                              H   (CH.sub.2).sub.2                                                                         H  H   base  0.01    0.63                                                                              1.25                    H         H   6-Cl                                                                              (CH.sub.2).sub.2                                                                         H  H   base  0.02    2.5 2.5                     H         5-CF.sub.3                                                                        H   (CH.sub.2).sub.2                                                                         H  H   base  0.02    0.31                                                                              1.25                    H         5-CH.sub.3                                                                        H   (CH.sub.2).sub.2                                                                         H  H   base  0.01    1.25                                                                              1.25                    H         H   H   (CH.sub.2).sub.2                                                                         4-F                                                                              H   base  0.02    0.31                                                                              0.16                    H         H   H   (CH.sub.2).sub.2                                                                         4-F                                                                              4-F base 1/2H.sub.2 O                                                                   0.02    0.63                                                                              0.63                    H         H   H   (CH.sub.2).sub.3                                                                         H  H   base  0.005   0.10                                                                              0.31                    H         5-Cl                                                                              H   (CH.sub.2).sub.3                                                                         H  H   base  0.01    0.63                                                                              1.25                    H         5-CH.sub.3                                                                        H   (CH.sub.2).sub.3                                                                         H  H   base  0.01    0.08                                                                              0.16                    H         H   6-Cl                                                                              (CH.sub.2).sub.3                                                                         H  H   base  0.04    0.63                                                                              0.63                    H         H   6-CH.sub.3                                                                        (CH.sub.2).sub.3                                                                         H  H   base  0.01    0.16                                                                              0.31                    H         H   7-Cl                                                                              (CH.sub.2).sub.3                                                                         H  H   base  0.08    ≧2.5                                                                       --                      H         5-Cl                                                                              6-Cl                                                                              (CH.sub.2).sub.3                                                                         H  H   base  ≧0.16                                                                          2.5 2.5                     H         5-CF.sub.3                                                                        H   (CH.sub.2).sub.3                                                                         H  H   base  0.02    0.31                                                                              0.31                     ##STR54##                                                                              H   H   (CH.sub.2).sub.3                                                                         H  H   base  0.01    0.16                                                                              0.31                    C.sub.2 H.sub.5OOC                                                                      H   H   (CH.sub.2).sub.3                                                                         H  H   2HCl.2H.sub.2 O                                                                     0.005   0.63                                                                              0.63                    (CH.sub.2).sub.2                                                              C.sub.6 H.sub.5CH.sub.2                                                                 H   H   (CH.sub.2).sub.3                                                                         H  H   2HCl  0.16    1.25                                                                              1.25                    CH.sub.3CO                                                                              H   H   (CH.sub.2).sub.3                                                                         H  H   base  0.005   0.10                                                                              0.31                    CH.sub.3NHCO                                                                            H   H   (CH.sub.2).sub.3                                                                         H  H   base  0.02    --  --                      CH.sub.3  H   H   (CH.sub.2).sub.3                                                                         H  H   2HCl.H.sub.2 O                                                                      0.01    1.25                                                                              2.5                     HOCH.sub.2                                                                              H   H   (CH.sub.2).sub.3                                                                         H  H   base  0.01    0.31                                                                              0.31                    C.sub.6 H.sub.5                                                                         5-Cl                                                                              H   (CH.sub.2).sub.3                                                                         H  H   2HCl.1/2H.sub.2 O                                                                   0.08    --  --                      H         H   H   (CH.sub.2).sub.3                                                                         4-F                                                                              H   base  0.01    0.31                                                                              0.31                    H         H   H   (CH.sub.2).sub.3                                                                         4-Cl                                                                             H   base  0.01    1.25                                                                              0.63                    H         H   H   (CH.sub.2).sub.3                                                                         3-Cl                                                                             H   base  0.01    0.63                                                                              1.25                    H         H   H   (CH.sub.2).sub.3                                                                         4-F                                                                              4-F base  0.01    0.31                                                                              0.16                    H         5-Cl                                                                              H   (CH.sub.2).sub.3                                                                         4-F                                                                              4-F base  0.04    1.25                                                                              1.25                    H         H   6-Cl                                                                              (CH.sub.2).sub.3                                                                         4-F                                                                              4-F base.H.sub.2 O                                                                      0.02    0.63                                                                              1.25                    H         H   H   (CH.sub.2).sub.3                                                                         2-F                                                                              4-Cl                                                                              base  0.02    0.31                                                                              1.25                    H         H   H   (CH.sub.2).sub.4                                                                         H  H   base  0.01    0.16                                                                              0.31                    H         H   H   (CH.sub.2).sub.4                                                                         4-F                                                                              4-F 2HCl.H.sub.2 O                                                                      0.01    0.16                                                                              0.31                                                        1/2C.sub.2 H.sub.5 OH                     H         H   H   (CH.sub.2).sub.5                                                                         H  H   2HCl.H.sub.2 O                                                                      0.01    0.63                                                                              2.5                     H         H   H   (CH.sub.2).sub.5                                                                         4-F                                                                              4-F 2HCl.H.sub.2 O                                                                      0.01    1.25                                                                              2.5                     H         H   H   (CH.sub.2).sub.6                                                                         H  H   base  0.01    1.25                                                                              2.5                     H         H   H                                                                                  ##STR55## 4-F                                                                              4-F base  0.02    1.25                                                                              1.25                    H         H   H   (CH.sub.2).sub.3                                                                         H  2-Cl                                                                              base  0.08    --  --                      H         H   H   (CH.sub.2).sub.3                                                                         4-Cl                                                                             4-Cl                                                                              base  0.16    <2.5                                                                              <2.5                    H         H   H   (CH.sub.2).sub.3                                                                         H  4-Br                                                                              base  0.16    <2.5                                                                              <2.5                    H         H   H   (CH.sub.2).sub.3                                                                         H  2-F base  0.02    <2.5                                                                              <2.5                    H         H   H   (CH.sub.2).sub.3                                                                         4-F                                                                              4-CH.sub.3                                                                        base  0.16    <2.5                                                                              < 2.5                   H         H   H   (CH.sub.2).sub.3                                                                         H  4-CH.sub.3                                                                        base  0.08    <2.5                                                                              <2.5                    H         H   H   (CH.sub.2).sub.3                                                                         H  4-NO.sub.2                                                                        base  0.16    <2.5                                                                              <2.5                    HOOCCH.sub.2                                                                            H   H   (CH.sub.2).sub.3                                                                         H  H   base 1/2H.sub.2 O                                                                   0.08    <2.5                                                                              <2.5                    __________________________________________________________________________

                                      TABLE I-b                                   __________________________________________________________________________     ##STR56##                                                                                                             Histamine in                                                                  "vitro" (ileum)                                                                       Anaphylaxis in guinea                                                         pigs                                                         Base or Salt                                                                           effective conc.                                                                       oral effective dose in                                                        mg/kg                        M         R.sup.1                                                                           C.sub.n H.sub.2n                                                                          R.sup.6                                                                          R.sup.7                                                                          form     in mg/l Survival                                                                           Histamine               __________________________________________________________________________                                                          oedema                  H         H   (CH.sub.2).sub.2                                                                          H  H  Base     0.005   1.25 1.25                    C.sub.2 H.sub.5                                                                         H   (CH.sub.2).sub.2                                                                          H  H  3HCl.H.sub.2 O                                                                         ≧0.16                                                                          --   --                      H         H   (CH.sub.2).sub.3                                                                          H  H  base     0.0025  0.08 0.16                    CH.sub.3S H   (CH.sub.2).sub.3                                                                          H  H  3HCl.H.sub.2 O                                                                         0.16    1.25 1.25                    CH.sub.3  H   (CH.sub.2).sub.3                                                                          H  H  base     0.02    2.5  2.5                     C.sub.6 H.sub.5                                                                         H   (CH.sub.2).sub.3                                                                          H  H  base     0.08    --   --                      HS        H   (CH.sub.2).sub.3                                                                          H  H  base     0.01    0.63 1.25                    cyclohexyl-                                                                             H   (CH.sub.2).sub.3                                                                          H  H  base     ≧0.16                                                                          2.5  2.5                     C.sub.6 H.sub.5CH.sub.2                                                                 H   (CH.sub.2).sub.3                                                                          H  H  3HCl.H.sub.2 O                                                                         ≧0.16                                                                          --   --                      CH.sub.3 OOCNH                                                                          H   (CH.sub.2).sub.3                                                                          H  H  base     ≦0.16                                                                          2.5  2.5                     H.sub.2 N H   (CH.sub.2).sub.3                                                                          H  H  base     ≦0.16                                                                          2.5  2.5                     CH.sub.3CONH                                                                            H   (CH.sub.2).sub.3                                                                          H  H  base     ≧0.16                                                                          2.5  --                      C.sub.2 H.sub.5                                                                         H   (CH.sub.2).sub.3                                                                          H  H  3HCl.H.sub.2 O                                                                         0.01    2.5  2.5                     cyclohexyl-                                                                             5-Cl                                                                              (CH.sub.2).sub.3                                                                          H  H  base     --      0.63 2.5                     C.sub.2 H.sub.5                                                                         5-Cl                                                                              (CH.sub.2).sub.3                                                                          H  H  3HCl.H.sub.2 O                                                                         0.01    --   --                      C.sub.6 H.sub.5CH.sub.2                                                                 5-Cl                                                                              (CH.sub.2).sub.3                                                                          H  H  3HCl.H.sub.2 O                                                                         --      2.5  --                      C.sub.6 H.sub.5                                                                         6-Cl                                                                              (CH.sub.2).sub.3                                                                          H  H  base     --      2.5  --                      cyclohexyl-                                                                             6-Cl                                                                              (CH.sub.2).sub.3                                                                          H  H  base     --      2.5  --                      H         H   (CH.sub.2).sub.3                                                                          4-F                                                                              H  base     0.005   0.31 0.31                    H         H   (CH.sub.2).sub.3                                                                          2-Cl                                                                             H  3HCl2H.sub.2 O                                                                         0.01    1.25 1.25                    H         H   (CH.sub.2).sub.3                                                                          4-Cl                                                                             H  base     0.01    0.08 0.31                    H         H   (CH.sub.2).sub.3                                                                          4-F                                                                              4-F                                                                              base H.sub.2 O                                                                         0.02    0.16 0.31                    H         H   (CH.sub.2).sub.4                                                                          H  H  base     0.0025  0.16 0.16                    CH.sub.3  H   (CH.sub.2).sub.4                                                                          H  H  base     0.005   1.25 1.25                    H         H   (CH.sub.2).sub.4                                                                          4-F                                                                              H  base     0.005   0.08 0.16                    H         H   (CH.sub.2).sub.4                                                                          3-Cl                                                                             H  3HCl.H.sub.2 O                                                                         0.01    1.25 1.25                                                    1/2CH.sub.3 CHOHCH.sub.3                      H         H   (CH.sub.2).sub.4                                                                          4-F                                                                              4-F                                                                              base     0.005   0.31 0.31                    H         H   CH.sub.2CH(CH.sub.3)CH.sub.2                                                              H  H  3HCl1/2H.sub.2 O                                                                       0.02    --   --                      H         H   CH.sub.2CH(CH.sub.3)CH.sub.2                                                              4-F                                                                              4-F                                                                              3HCl1/2H.sub.2 O                                                                       0.02    0.63 1.25                    __________________________________________________________________________

                  TABLE I-c                                                       ______________________________________                                         ##STR57##                                                                                          Anaphylaxis in                                                                guinea pigs                                                        Histamine in                                                                             oral effective                                                     "vitro" (ileum)                                                                          dose in mg/kg                                                            effective conc.     Histamine                                Y   Base or Salt form                                                                          in mg/l      Survival                                                                             oedema                                   ______________________________________                                        S   2 HCl.1/2 H.sub.2 O                                                                        0.01         1.25   1.25                                     O   2 HCl        0.01         0.63   2.5                                      ______________________________________                                    

                                      TABLE I-d                                   __________________________________________________________________________     ##STR58##                                                                                       Base or                                                                             Histamine in "vitro"                                                                     Anaphylaxis in guinea pigs                                   Salt  (ileum)    oral effective dose in mg/kg              B        C.sub.n H.sub.2n                                                                  R.sup.6                                                                          R.sup.7                                                                          form  effective dose in mg/l                                                                   Survival                                                                           Histamine oedema                     __________________________________________________________________________     ##STR59##                                                                             (CH.sub.2).sub.2                                                                  H  H  HCl   0.0025     0.31 0.16                                  ##STR60##                                                                             (CH.sub.2).sub.3                                                                  H  H  base  0.0025     0.63 1.25                                  ##STR61##                                                                             (CH.sub. 2).sub.4                                                                 H  H  base  0.005      0.63 0.31                                  ##STR62##                                                                             (CH.sub.2).sub.2                                                                  4-F                                                                              4-F                                                                              HCl.1/2 H.sub.2 O                                                                   0.0025     0.31 0.31                                  ##STR63##                                                                             (CH.sub.2).sub.3                                                                  4-F                                                                              4-F                                                                              HCl.1/2 H.sub.2 O                                                                   0.0025     0.63 0.63                                  ##STR64##                                                                             (CH.sub.2).sub.3                                                                  H  H  base  0.0025     0.16 0.16                                 __________________________________________________________________________

                                      TABLE I-e                                   __________________________________________________________________________     ##STR65##                                                                                         Histamine in "vitro"                                                     Base or                                                                            (ileum)   Anaphylaxis in guinea pigs                                     Salt effective dose in                                                                       oral effective dose in mg/kg                   Ar.sup.1                                                                             Ar.sup.2 Form mg/l      Survival                                                                           Histamine oedema                          __________________________________________________________________________    C.sub.6 H.sub.5                                                                      2-pyridinyl                                                                            base 0.16      --   2.5                                       C.sub.6 H.sub.5                                                                      3-pyridinyl                                                                            base 0.08      --   <2.5                                      C.sub.6 H.sub.5                                                                      2,5-(CH.sub.3).sub.2C.sub.6 H.sub.3                                                    base 0.16      --   --                                        4-ClC.sub.6 H.sub.4                                                                  3-pyridinyl                                                                            base 0.08      1.25 2.5                                       4-FC.sub.6 H.sub.4                                                                   3-pyridinyl                                                                            base 0.08      <2.5 <2.5                                      4-FC.sub.6 H.sub.4                                                                   4-pyridinyl                                                                            base 0.16      --   ≦2.5                               __________________________________________________________________________

The following examples are intended to illustrate but not to limit thescope of the present invention. Unless otherwise stated all partstherein are by weight.

EXAMPLE I

To a stirred and hot mixture of 54 parts of1,3-dihydro-1-(phenylmethyl)-2H-benzimidazol-2-one, 47.25 parts of1-bromo-3-chloropropane and 6 parts ofN,N,N-triethylbenzenemethanaminium chloride are added dropwise 450 partsof a sodium hydroxide solution 60% at 60° C. Upon completion, stirringis continued for 6 hours at 60° C. The reaction mixture is cooled andpoured onto water. The oily product is extracted with trichloromethane.The extract is dried, filtered and evaporated. The residue iscrystallized from 2,2'-oxybispropane, yielding, after drying,1-(3-chloropropyl)-1,3-dihydro-3-(phenylmethyl)-2H-benzimidazol-2-one.

EXAMPLE II

To a stirred and hot (50° C.) mixture of 47 parts of1,3-dihydro-6-methyl-1-(1-methylethenyl)-2H-benzimidazol-2-one and 5parts of N,N,N-triethylbenzenemethanaminium chloride in 300 parts of asodium hydroxide solution 50% are added 79 parts of1-bromo-3-chloropropane. The whole is heated to 60° C.: exothermicreaction (temperature rises to 75° C.). Stirring is continued for onehour while cooling to keep the temperature between 60° and 70° C. Thereaction mixture is cooled and poured onto crushed ice. The product isextracted with methylbenzene. The extract is washed three times withwater, dried, filtered and evaporated. The oily residue is distilled,yielding1-(3-chloropropyl)-1,3-dihydro-5-methyl-3-(1-methylethenyl)-2H-benzimidazol-2-one;bp. 140° C. at 0.015 mm. pressure.

EXAMPLE III

To a stirred and hot (±50° C.) mixture of 34 parts of1,3-dihydro-5-methyl-1-(1-methylethenyl)-2H-benzimidazol-2-one, 5 partsof N,N,N-triethylbenzenemethanaminium chloride and 300 parts of a sodiumhydroxide solution 50% are added 57 parts of 1-bromo-3-chloropropane(exothermic reaction: temperature rises to 70° C.). The whole is stirredfor one hour at 65°-70° C. The reaction mixture is cooled and pouredonto crushed ice. The product is extracted with methylbenzene. Theextract is washed three times with water, dried, filtered andevaporated. The oily residue is distilled, yielding3-(3-chloropropyl)-1,3-dihydro-5-methyl-1-(1-methylethenyl)-2H-benzimidazol-2-one;bp. 140° C. at 0.02 mm. pressure.

EXAMPLE IV

To a stirred solution of 7 parts of6-chloro-1,3-dihydro-1-phenyl-2H-benzimidazol-2-one in 67.5 parts ofN,N-dimethylformamide is added portionwise 1 part of a sodium hydridedispersion 78%. After stirring for 2 hours at room temperature, thereare added dropwise (slowly) 4.75 parts of 1-bromo-3-chloropropane. Uponcompletion, stirring is continued first for two hours at roomtemperature and further for one hour at 60° C. The reaction mixture ispoured onto water and the product is extracted with methylbenzene. Theextract is dried, filtered and evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and 5% of methanol as eluent. The pure fractions arecollected and the eluent is evaporated, yielding5-chloro-1-(3-chloropropyl)-1,3-dihydro-3-phenyl-2H-benzimidazol-2-oneas a residue.

EXAMPLE V

To a stirred and hot (50° C.) mixture of 28.3 parts of1,3-dihydro-1-(1-methylethenyl)-2H-benzimidazol-2-one, 5 parts ofN,N,N-triethylbenzenemethanaminium chloride and 225 parts of a sodiumhydroxide solution 60% are added dropwise, during a 30 minutes-period,33.7 parts of 1-bromo-4-chlorobutane. Upon completion, stirring iscontinued for 5 hours at 60° C. The reaction mixture is cooled, water isadded and the product is extracted with methylbenzene. The extract isdried, filtered and evaporated, yielding1-(4-chlorobutyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas a residue.

EXAMPLE VI

To a stirred suspension of 3.2 parts of a sodium hydride dispersion 70%in 9 parts of N,N-dimethylformamide is added dropwise, during a 2hours-period, a mixture of 17.4 parts of1,3-dihydro-1-(1-methylethenyl)-2H-benzimidazol-2-one, 70.5 parts of1,5-dichloropentane and 45 parts of N,N-dimethylformamide at 25°-30° C.Upon completion, stirring is continued for 2 hours at room temperature.The reaction mixture is filtered over hyflo and the filtrate isevaporated. The residue is taken up in 90 parts of methylbenzene and thewhole is stirred with activated charcoal. The latter is filtered off.The filtrate is washed with water, dried, filtered and evaporated in anoil-bath at 120° C. (water-jet), yielding1-(5-chloropentyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas a residue.

EXAMPLE VII

To a stirred mixture of 3.2 parts of a sodium hydride dispersion 70% in9 parts of N,N-dimethylformamide is added dropwise (slowly), during a 2hours-period, a mixture of 17.4 parts of1,3-dihydro-1-(1-methylethenyl)-2H-benzimidazol-2-one, 77.5 parts of1,6-dichlorohexane and 36 parts of N,N-dimethylformamide. Uponcompletion, stirring is continued overnight at room temperature. Thereaction mixture is filtered over hyflo and the N,N-dimethylformamide isevaporated in vacuo. The excess of 1,6-dichlorohexane is distilled offin an oil-bath with water-jet. The residue is dissolved in methylbenzeneand the solution is stirred with activated charcoal. The latter isfiltered off over hyflo and the filtrate is evaporated, yielding1-(6-chlorohexyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas an oily residue.

EXAMPLE VIII

To a stirred mixture of 5 parts of4-chloro-1,3-dihydro-3-(3-hydroxypropyl)-2H-benzimidazol-2-one and 75parts of trichloromethane are added dropwise 8 parts of sulfinylchloride. Upon completion, stirring is continued for 3 hours at refluxtemperature. The reaction mixture is cooled and evaporated. The residueis stirred in a small amount of 4-methyl-2-pentanone. The product isfiltered off and dried, yielding4-chloro-3-(3-chloropropyl)-1,3-dihydro-2H-benzimidazol-2-one.

EXAMPLE IX

To a stirred mixture of 13.2 parts of 2-methyl-1H-benzimidazole, 2 partsof N,N,N-triethylbenzenemethanaminium chloride and 150 parts of a sodiumhydroxide solution 60% are added 30 parts of 1-bromo-3-chloropropane. Tostart the reaction, the whole is heated to about 40° C., whereupon thetemperature rises to 50° C. (exothermic reaction). Stirring at about 50°C. is continued for 30 minutes. The reaction mixture is poured ontowater and the product is extracted with methylbenzene. The extract isdried, filtered and evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (90:10) as eluent. The pure fractions arecollected and the eluent is evaporated, yielding1-(3-chloropropyl)-2-methyl-1H-benzimidazole as a residue.

EXAMPLE X

A mixture of 20 parts of 2-cyclohexyl-1H-benzimidazole, 2 parts ofN,N,N-triethylbenzenemethanaminium chloride, 225 parts of a sodiumhydroxide solution 50% and 140 parts of tetrahydrofuran is stirred andheated to 40° C. Then there are added 31.5 parts of1-bromo-3-chloropropane and stirring is continued for 15 minutes at 60°C. The reaction mixture is cooled, methylbenzene is added and the layersare separated. The aqueous phase is extracted with methylbenzene. Thecombined methylbenzene-phases are washed with water, dried, filtered andevaporated. The residue is purified by column-chromatography over silicagel using a mixture of trichloromethane and methanol (95:5) as eluent.The pure fractions are collected and the eluent is evaporated, yielding1-(3-chloropropyl)-2-cyclohexyl-1H-benzimidazole as an oily residue.

EXAMPLE XI

To a stirred mixture of 29.2 parts of 2-ethyl-1H-benzimidazole, 5 partsof N,N,N-triethylbenzenemethanaminium chloride and 300 parts of a sodiumhydroxide solution 60% are added 60 parts of 1-bromo-3-chloropropane.The whole is heated to about 65° C. and stirring is continued for 30minutes at this temperature. Methylbenzene is added and the whole ispoured onto water. The organic phase is separated, dried, filtered andevaporated. The residue is purified twice by column-chromatography oversilica gel using a mixture of trichloromethane and methanol (90:10) aseluent. The pure fractions are collected and the eluent is evaporated,yielding 1-(3-chloropropyl)-2-ethyl-1H-benzimidazole as a residue.

EXAMPLE XII

To a stirred and warm (40° C.) mixture of 9.5 parts of 1H-benzimidazole,2 parts of N,N,N-triethylbenzenemethanaminium chloride, 225 parts of asodium hydroxide solution 50% and 90 parts of tetrahydrofuran are added17 parts of 1-bromo-3-chloro-2-methylpropane. The whole is heated toabout 60° C. and stirring is continued for 15 minutes at thistemperature. The reaction mixture is cooled and the product is extractedwith trichloromethane. The extract is dried, filtered and evaporated.The oily residue is purified by column-chromatography over silica gelusing a mixture of trichloromethane and methanol (95:5) as eluent. Thepure fractions are collected and the eluent is evaporated, yielding1-(3-chloro-2-methylpropyl)-1H-benzimidazole as an oily residue.

EXAMPLE XIII

A mixture of 38.8 parts of 2-phenyl-1H-benzimidazole, 44 parts of asodium methoxide solution 30% and 320 parts of 2-propanol is stirred andheated for 15 minutes at 50° C. After cooling, there are added 47.25parts of 1-bromo-3-chloropropane. The whole is stirred and refluxed for3 hours. The reaction mixture is evaporated. The residue is diluted withwater and the product is extracted with methylbenzene. The extract isdried, filtered and evaporated, yielding1-(3-chloropropyl)-2-phenyl-1H-benzimidazole as a residue.

EXAMPLE XIV

To a stirred mixture of 13.2 parts of 2-methyl-1H-benzimidazole, 3 partsof N,N,N-triethylbenzenemethanaminium chloride and 225 parts of a sodiumhydroxide solution 60% are added 25 parts of 1,4-dichlorobutane. Thewhole is heated to about 100° C. and stirring is continued for one hourat this temperature. The reaction mixture is cooled and poured ontoice-water. The product is extracted with methylbenzene. The extract isdried, filtered and evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (90:10) as eluent. The pure fractions arecollected and eluent is evaporated, yielding1-(4-chlorobutyl)-2-methyl-1H-benzimidazole as a residue.

EXAMPLE XV

To a stirred mixture of 45 parts of5-chloro-2(phenylmethyl)-1H-benzimidazole-1-propanol and 225 parts oftrichloromethane are added dropwise 29.75 parts of sulfinyl chloride.Upon completion, stirring is continued for 6 hours at refluxtemperature. The reaction mixture is evaporated and the residue is takenup in water. The product is extracted with trichloromethane. The extractis dried, filtered and evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (98:2) as eluent. The pure fractions arecollected and the eluent is evaporated, yielding5-chloro-1-(3-chloropropyl)-2-(phenylmethyl)-1H-benzimidazole as a solidresidue.

EXAMPLE XVI

A mixture of 20 parts of 3-[(2-amino-4-chlorophenyl)amino]-1-propanol,50 parts of acetic acid and 150 parts of a hydrochloric acid solution 4N is stirred and refluxed overnight. The reaction mixture is cooled andevaporated. The residue is dissolved in water and the solution isalkalized with ammonium hydroxide. The product is extracted withtrichloromethane. The extract is dried, filtered and evaporated. Theresidue is crystallized from a mixture of 4-methyl-2-pentanone and2,2'-oxybispropane, yielding5-chloro-2-methyl-1H-benzimidazole-1-propanol.

To a stirred mixture of 6.5 parts of5-chloro-2-methyl-1H-benzimidazole-1-propanol and 120 parts oftrichloromethane are added dropwise 12 parts of sulfinyl chloride. Uponcompletion, the whole is heated to reflux and stirring is continued for3 hours at reflux temperature. The reaction mixture is cooled andevaporated. Water is added to the residue and the mixture is treatedwith activated charcoal. The latter is filtered off and the filtrate isalkalized with ammonium hydroxide. The product is extracted withtrichloromethane. The extract is dried, filtered and evaporated. Theresidue is crystallized from 2,2'-oxybispropane. The product is filteredoff and dried, yielding5-chloro-1-(3-chloropropyl)-2-methyl-1H-benzimidazole.

EXAMPLE XVII

A mixture of 30 parts of 3-[(2-amino-4-chlorophenyl)amino]-1-propanol,20 parts of propanoic acid and 200 parts of a hydrochloric acid solution4 N is stirred and refluxed for 3 hours. The reaction mixture is cooled,water and crushed ice are added and the whole is treated with activatedcharcoal. The latter is filtered off and the filtrate is alkalized withammonium hydroxide. The product is extracted with methylbenzene. Theextract is dried, filtered and evaporated. The residue is crystallizedfrom 4-methyl-2-pentanone. The product is filtered off and dried,yielding 5-chloro-2-ethyl-1H-benzimidazole-1-propanol.

To a stirred mixture of 4 parts of5-chloro-2-ethyl-1H-benzimidazole-1-propanol and 150 parts oftrichloromethane are added dropwise 9.6 parts of sulfinyl chloride. Uponcompletion, the whole is heated to reflux and stirring is continued for2 hours at reflux temperature. The reaction mixture is cooled andevaporated. The residue is taken up in water and stirred with activatedcharcoal. The latter is filtered off and the filtrate is alkalized withammonium hydroxide. The product is extracted with trichloromethane. Theextract is dried, filtered and evaporated, yielding5-chloro-1-(3-chloropropyl)-2-ethyl-1H-benzimidazole.

EXAMPLE XVIII

To a stirred and refluxing (water-separator) mixture of 30 parts of3-[(2-amino-4-chlorophenyl)amino]-1-propanol and 0.1 parts of4-methylbenzenesulfonic acid in 405 parts of methylbenzene is addeddropwise a solution of 34 parts of cyclohexanecarboxaldehyde in 45 partsof methylbenzene. Upon completion, stirring is continued for one hour atreflux temperature and with water-separator. The methylbenzene isremoved by evaporation in vacuo and the residue is triturated in2,2'-oxybispropane. The product is filtered off and dried, yielding5-chloro-2-cyclohexyl-1H-benzimidazole-1-propanol; mp. 95° C.

To a stirred mixture of 21 parts of5-chloro-2-cyclohexyl-1H-benzimidazole-1-propanol in 225 parts oftrichloromethane are added dropwise 40 parts of sulfinyl chloride(exothermic reaction). Upon completion, stirring is continued for 2hours at reflux temperature. The reaction mixture is evaporated and theresidue is dissolved in boiling water. The solution is treated withactivated charcoal. The latter is filtered off till a clear filtrate isobtained. After cooling in an ice-bath, the precipitated product isfiltered off and dried, yielding5-chloro-1-(3-chloropropyl)-2-cyclohexyl-1H-benzimidazole hydrochloride;mp. 211.7° C.

EXAMPLE XIX

To a stirred mixture of 40 parts of2-(phenylmethyl)-1H-benzimidazole-1-propanol and 225 parts oftrichloromethane are added dropwise 30 parts of sulfinyl chloride. Uponcompletion, stirring is continued for 4 hours at reflux temperature. Thereaction mixture is evaporated and the residue is boiled in water. Thesolution is filtered over hyflo and the filtrate is alkalized withammonium hydroxide. The product is extracted with trichloromethane. Theextract is dried, filtered and evaporated. The residue is crystallizedfrom a mixture of 4-methyl-2-pentanone and 2,2'-oxybispropane. Theproduct is filtered off and dried, yielding1-(3-chloropropyl)-2-(phenylmethyl)-1H-benzimidazole; mp. 112° C.

EXAMPLE XX

A mixture of 30 parts of 3-[(2-amino-4-chlorophenyl)amino]-1-propanol,44.8 parts of sodium α-hydroxybenzeneethanesulfonate and 120 parts ofethanol is stirred and refluxed for 30 minutes. The reaction mixture isevaporated and the residue is taken up in water. The oily product isextracted with trichloromethane. The extract is dried, filtered andevaporated, yielding5-chloro-2-(phenylmethyl)-1H-benzimidazole-1-propanol as a residue.

EXAMPLE XXI

To a stirred mixture of 93 parts of 3-(2-aminophenyl) amino-1-propanol,45.5 parts of potassium hydroxide and 600 parts of an ethanol solution85% in water are added dropwise 60.8 parts of carbon disulfide. Uponcompletion, stirring is continued for 6 hours at reflux temperature. Thereaction mixture is evaporated and the residue is taken up in 1500 partsof water. The whole is filtered over hyflo and the filtrate is acidifiedwith acetic acid. The oily product solidifies on scratching. It isfiltered off, washed with water and dried, yielding2-mercapto-1H-benzimidazole-1-propanol; mp. 110° C.

A mixture of 20.8 parts of 2-mercapto-1H-benzimidazole-1-propanol, 15.62parts of iodomethane and 120 parts of methanol is stirred overnight atroom temperature. The reaction mixture is evaporated and the residue isdissolved in 500 parts of water. The solution is filtered over hyflo andthe filtrate is alkalized with solid potassium hydroxide. The oilyproduct is extracted with trichloromethane. The extract is dried,filtered and evaporated, yielding2-(methylthio)-1H-benzimidazole-1-propanol as a residue.

To a stirred mixture of 19 parts of2-(methylthio)-1H-benzimidazole-1-propanol, 15.2 parts ofN,N-diethylethanamine and 195 parts of dichloromethane are addeddropwise 11.5 parts of methanesulfonyl chloride. Upon completion,stirring is continued for one hour at reflux. After cooling, water isadded and the layers are separated. The organic phase is dried, filteredand evaporated, yielding 3-[2-(methylthio)-1H-benzimidazol-1-yl]propylmethanesulfonate as an oily residue.

EXAMPLE XXII

A mixture of 40 parts of 3-[(2-amino-5-chlorophenyl)amino]-1-propanol,87 parts of sodium α-hydroxycyclohexanemethanesulfonate and 200 parts ofethanol is stirred and refluxed for 10 minutes. The reaction mixture isdiluted with water and the solvent is evaporated. The residue isextracted a few times with trichloromethane. The combined extracts aredried, filtered and evaporated. The oily residue is triturated in2,2'-oxybispropane: a sticky tar precipitates. The 2,2'-oxybispropane isdecanted and upon stirring at room temperature, the product is allowedto precipitate. It is filtered off and dried, yielding6-chloro-2-cyclohexyl-1H-benzimidazole-1-propanol; mp. 120.1° C.

To a stirred mixture of 50 parts of6-chloro-2-cyclohexyl-1H-benzimidazole-1-propanol in 375 parts oftrichloromethane are added dropwise 60 parts of sulfinyl chloride(exothermic reaction). Upon completion, stirring is continued for 2hours at reflux temperature. The reaction mixture is evaporated and thesemi-solid residue is dissolved in hot water. The solution is stirredwith activated charcoal. The latter is filtered hot over hyflo and thefiltrate is stirred in an ice-bath. The precipitated product is filteredoff and dried, yielding6-chloro-1-(3-chloropropyl)-2-cyclohexyl-1H-benzimidazole hydrochloride;mp. 227.5° C.

EXAMPLE XXIII

To a stirred and refluxing mixture of 7 parts of2-ethyl-1H-benzimidazole-1-ethanol and 150 parts of trichloromethane areadded dropwise 16 parts of sulfinyl chloride. Upon completion, the wholeis heated to reflux and stirring is continued for 2 hours at refluxtemperature. The reaction mixture is cooled and evaporated. Water isadded to the residue and the whole is stirred with activated charcoal.The latter is filtered off and the filtrate is alkalized. The product isextracted with trichloromethane. The extract is dried, filtered andevaporated. The residue is crystallized from 2,2'-oxybispropane. Theproduct is filtered off and dried, yielding1-(2-chloroethyl)-2-ethyl-1H-benzimidazole.

EXAMPLE XXIV

A mixture of 30 parts of 1H-benzimidazole, 49 parts of2-(4-chlorobutoxy)-tetrahydro-2H-pyran, 21 parts of potassium hydroxideand 200 parts of ethanol is stirred and refluxed overnight. The reactionmixture is cooled to room temperature, filtered and the filtrate isevaporated. The residue is stirred in water and acidified with a dilutedhydrochloric acid solution. The whole is stirred and heated for 30minutes in a water-bath. After cooling to room temperature, the productis extracted with methylbenzene. The aqueous phase is separated andalkalized with ammonium hydroxide. The product is extracted witdichloromethane. The extract is dried, filtered and evaporated, yielding1H-benzimidazole-1-butanol as an oily residue.

To a stirred mixture of 50 parts of 1H-benzimidazole-1-butanol and 375parts of trichloromethane are added dropwise 35.2 parts of sulfinylchloride. Upon completion, stirring is continued for 3 hours at refluxtemperature. The reaction mixture is evaporated. The residue is taken upin trichloromethane. The whole is washed with ammonium hydroxide and thesolvent is evaporated. The residue is purified by column-chromatographyover silica gel using trichloromethane as eluent. The pure fractions arecollected and the eluent is evaporated, yielding1-(4-chlorobutyl)-1H-benzimidazole as an oily residue.

EXAMPLE XXV

A mixture of 113.2 parts of 1,2,4-trichloro-5-nitrobenzene, 75 parts of3-amino-1-propanol, 0.2 parts of potassium iodide and 200 parts ofbutanol is stirred and refluxed overnight. The butanol is removed byevaporation in vacuo and water is added to the residue. The product isextracted with 4-methyl-2-pentanone. The extract is washed a few timeswith water, dried, filtered and evaporated. The oily residue is purifiedby column-chromatography over silica gel using a mixture oftrichloromethane and 5% of methanol as eluent. The pure fractions arecollected and the eluent is evaporated. The residue is triturated in2,2'-oxybispropane. The product is filtered off and crystallized from amixture of 2,2'-oxybispropane and 2-propanol, yielding3-[(4,5-dichloro-2-nitrophenyl)amino]-1-propanol; mp. 97° C.

To a stirred mixture of 10 parts of3-[(4,5-dichloro-2-nitrophenyl)amino]-1-propanol and 75 parts oftrichloromethane are added dropwise 11.2 parts of sulfinyl chloride.Upon completion, stirring is continued for 4 hours at refluxtemperature. The reaction mixture is evaporated and the residue ispurified by column-chromatography over silica gel using a mixture oftrichloromethane and methanol (98:2) as eluent. The pure fractions arecollected and the eluent is evaporated. The residue is crystallized from2,2'-oxybispropane. The product is filtered off and dried, yielding4,5-dichloro-N-(3-chloropropyl)-2-nitrobenzenamine; mp. 78° C.

A mixture of 6.5 parts of 4,5-dichloro-N-(3-chloropropyl)2-nitrobenzenamine, 5.6 parts of 1-(diphenylmethyl)piperazine, 5.3 partsof sodium carbonate, 0.1 parts of potassium iodide and 200 parts of4-methyl-2-pentanone is stirred and refluxed overnight. The reactionmixture is cooled to room temperature and water is added. The organicphase is separated, dried, filtered and evaporated, yieldingN-(4,5-dichloro-2-nitrophenyl)-4-(diphenylmethyl)-1-piperazinepropanamineas a residue.

A mixture of 8 parts ofN-(4,5-dichloro-2-nitrophenyl)-4-(diphenylmethyl)-1-piperazinepropanamineand 200 parts of methanol is hydrogenated at normal pressure and at roomtemperature with 2 parts of Raney-nickel catalyst. After the calculatedamount of hydrogen is taken up, the catalyst is filtered off and thefiltrate is evaporated, yielding 4,5-dichloro-N¹-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,2-benzenediamine as anoily residue.

EXAMPLE XXVI

A mixture of 100 parts of 1-chloro-2-nitro-4-(trifluoromethyl)benzene,90 parts of 3-amino-1-propanol and 200 parts of butanol is stirred andheated till reflux. Stirring at reflux is continued overnight. Thereaction mixture is cooled and evaporated. Water is added to the residueand the whole is acidified with a hydrochloric acid solution. Theproduct is extracted with methylbenzene. The extract is dried, filteredand evaporated. The solid residue is crystallized from petroleumether.The product is filtered off and dried, yielding3-{[2-nitro-4-(trifluoromethyl)phenyl]amino}-1-propanol.

To a stirred mixture of 26 parts of3-{[2-nitro-4-(trifluoromethyl)phenyl]amino}-1-propanol and 150 parts oftrichloromethane are added dropwise 40 parts of sulfinyl chloride. Uponcompletion, stirring is continued overnight at reflux temperature. Thereaction mixture is evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5) as eluent. The pure fractions arecollected and the eluent is evaporated, yieldingN-(3-chloropropyl)-2-nitro-4-(trifluoromethyl)benzenamine as a residue.

A mixture of 10 parts ofN-(3-chloropropyl)-2-nitro-4-(trifluoromethyl)benzenamine, 8.11 parts of1-(diphenylmethyl)piperazine, 8.37 parts of sodium carbonate, 0.1 partsof potassium iodide and 200 parts of 4-methyl-2-pentanone is stirred andrefluxed overnight. The reaction mixture is cooled and water is added.The organic phase is separated, washed with water, dried, filtered andevaporated. The oily residue is crystallized from 2-propanol. Theproduct is filtered off and dried, yielding4-(diphenylmethyl)-N-[2-nitro-4-(trifluoromethyl)phenyl]-1-piperazinepropanamine;mp. 113.7° C.

A mixture of 15 parts of4-(diphenylmethyl)-N-[2-nitro-4-(trifluoromethyl)phenyl]-1-piperazinepropanaminein 240 parts of methanol is hydrogenated at normal pressure and at roomtemperature with 2 parts of Raney-nickel catalyst. After the calculatedamount of hydrogen is taken up, the catalyst is filtered off and thefiltrate is evaporated, yielding N¹-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-4-(trifluoromethyl)-1,2-benzenediamine.

EXAMPLE XXVII

To a stirred mixture of 39.2 parts of 3-(2-nitrophenyl)amino-1-propanoland 225 parts of trichloromethane are added dropwise 35.7 parts ofsulfinyl chloride (exothermic reaction: temperature rises to 45° C.)Upon completion, stirring is continued for 6 hours at refluxtemperature. The reaction mixture is evaporated, yieldingN-(3-chloropropyl)-2-nitrobenzenamine as a residue.

A mixture of 21.5 parts of N-(3-chloropropyl)-2-nitrobenzenamine, 22.68parts of 1-(diphenylmethyl)piperazine, 20 parts of N,N-diethylethanamineand 180 parts of N,N-dimethylacetamide is stirred and heated for 6 hoursat 100° C. The reaction mixture is evaporated and the residue is takenup in water. The oily product is extracted with trichloromethane. Theextract is dried, filtered and evaporated. The residue is crystallizedfrom a mixture of 2-propanol, ethanol and 2,2'-oxybispropane. Theproduct is filtered off and dried, yielding4-(diphenylmethyl)-N-(2-nitrophenyl)-1-piperazinepropanaminehydrochloride; mp. 228° C.

A mixture of 15 parts of 4-(diphenylmethyl)N-(2-nitrophenyl)-1-piperazinepropanamine hydrochloride in 160 parts ofmethanol is hydrogenated at normal pressure and at room temperature with5 parts of Raney-nickel catalyst. After the calculated amount ofhydrogen is taken up, the catalyst is filtered off over hyflo and thefiltrate is evaporated. The solid residue is crystallized from a mixtureof 2-propanol and 2,2'-oxybispropane. The product is filtered off anddried, yieldingN-(2-aminophenyl)-4-(diphenylmethyl)-1-piperazinepropanaminehydrochloride; mp. 223.1° C.

EXAMPLE XXVIII

A mixture of 50 parts of 1-chloro-2-nitro-4-(trifluoromethyl)benzene, 37parts of 2-aminoethanol and 100 parts of 1-butanol is stirred andrefluxed overnight. The reaction mixture is cooled and evaporated. Theresidue is taken up in a diluted hydrochloric acid solution. The productis extracted with methylbenzene. The layers are separated and theaqueous phase is extracted with methylbenzene. The combinedmethylbenzene-phases are washed successively with a diluted hydrochloricacid solution and twice with water, dried, filtered and evaporated. Thesolid residue is crystallized from petroleumether. The product isfiltered off and dried, yielding2-{[2-nitro-4-(trifluoromethyl)phenyl]amino}ethanol; mp. 74.9° C.

To a stirred mixture of 12.5 parts of2-{[2-nitro-4-(trifluoromethyl)phenyl]amino}ethanol and 150 parts oftrichloromethane are added dropwise 7.5 parts of sulfinyl chloride. Uponcompletion, stirring is continued for 2 hours at reflux temperature. Thereaction mixture is evaporated and the residue is crystallized from2,2'-oxybispropane. The product is filtered off and dried, yieldingN-(2-chloroethyl)-2-nitro-4-(trifluoromethyl)benzenamine.

A mixture of 9 parts ofN-(2-chloroethyl)-2-nitro-4-(trifluoromethyl)benzenamine, 7.65 parts of1-(diphenylmethyl)piperazine, 7.9 parts of sodium carbonate, 0.1 partsof potassium iodide and 200 parts of 4-methyl-2-pentanone is stirred andrefluxed overnight. The reaction mixture is cooled, water is added andthe layers are separated. The organic phase is dried, filtered andevaporated. The residue is crystallized from a mixture of2,2'-oxybispropane and 2-propanol. The product is filtered off anddried, yielding4-(diphenylmethyl)-N-[2-nitro-4-(trifluoromethyl)phenyl]-1-piperazineethanamine;mp. 152.1° C.

A mixture of 7.5 parts of4-(diphenylmethyl)-N-[2-nitro-4-(trifluoromethyl)phenyl]-1-piperazineethanaminein 200 parts of methanol is hydrogenated at normal pressure and at roomtemperature with 5 parts of Ra/Ni. After the calculated amount ofhydrogen is taken up, the catalyst is filtered off and the filtrate isevaporated, yielding N¹-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-4-(trifluoromethyl)-1,2-benzenediamineas an oily residue.

EXAMPLE XXIX

A mixture of 70.4 parts of 1-(phenylmethyl)piperazine, 39.4 parts of1-(2-chloroethyl)-1,3-dihydro-2H-benzimidazol-2-one and 360 parts ofmethylbenzene is stirred and refluxed overnight. The reaction mixture iscooled, water is added and the layers are separated. Themethylbenzene-phase is washed three times with water, dried, filteredand evaporated. The solid residue is purified by column-chromatographyover silica gel using a mixture of trichloromethane and methanol (95:5)as eluent. The pure fractions are collected and the eluent isevaporated. The residue is boiled in 2,2'-oxybispropane. The whole iscooled on an ice-bath. The product is filtered off and crystallized froma mixture of 2,2'-oxybispropane and a small amount of 2-propanol,yielding1,3-dihydro-1-{2-[4-(phenylmethyl)-1-piperazinyl]ethyl}-2H-benzimidazol-2-one;mp. 136.5° C.

A mixture of 79 parts of1,3-dihydro-1-{2-[4-(phenylmethyl)-1-piperazinyl]ethyl}-2H-benzimidazol-2-oneand 320 parts of methanol is hydrogenated at normal pressure and at roomtemperature with 10 parts of palladium-on-charcoal catalyst 10%. Afterthe calculated amount of hydrogen is taken up, the catalyst is filteredoff and the filtrate is evaporated. The oily residue is alkalized withammonium hydroxide and a small amount of water is added. The product isextracted with trichloromethane. The extract is dried, filtered andevaporated. The oily residue solidifies on triturating in4-methyl-2-pentanone. The product is filtered off and dried, yielding1,3-dihydro-1-[2-(1-piperazinyl)ethyl]-2H-benzimidazol-2-one; mp. 122.6°C.

EXAMPLE XXX

A mixture of 60.5 parts of1-(3-chloropropyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one,31.68 parts of 1-(phenylmethyl)piperazine, 21.2 parts of sodiumcarbonate, 0.1 parts of potassium iodide and 400 parts of4-methyl-2-pentanone is stirred and refluxed for 20 hours withwater-separator. The reaction mixture is cooled, water is added and thelayers are separated. The organic phase is dried, filtered andevaporated, yielding1,3-dihydro-1-(1-methylethenyl)-3-{3-[4-(phenylmethyl)-1-piperazinyl]propyl}-2H-benzimidazol-2-oneas a residue.

To a stirred solution of 70 parts of1,3-dihydro-1-(1-methylethenyl)-3-{3-[4-(phenylmethyl)-1-piperazinyl]propyl}-2H-benzimidazol-2-onein 240 parts of ethanol are added 55 parts of a hydrochloric acidsolution 6 N. The whole is stirred for 2 hours at 40°-50° C. Thereaction mixture is evaporated and the residue is taken up in a dilutedammonium hydroxide solution. The oily product is extracted withtrichloromethane. The extract is dried, filtered and evaporated,yielding1,3-dihydro-1-{3-[4-(phenylmethyl)-1-piperazinyl]propyl}-2H-benzimidazol-2-oneas a residue.

A mixture of 63 parts of1,3-dihydro-1-{3-[4-(phenylmethyl)-1-piperazinyl]propyl}-2H-benzimidazol-2-onein 400 parts of methanol is hydrogenated at normal pressure and at roomtemperature with 10 parts of palladium-on-charcoal catalyst 10%. Afterthe calculated amount of hydrogen is taken up, the catalyst is filteredoff over hyflo and the filtrate is evaporated. The residue iscrystallized from a mixture of 4-methyl-2-pentanone and 2-propanol. Theproduct is filtered off and dried, yielding1,3-dihydro-1-[3-(1-piperazinyl)propyl]-2H-benzimidazol-2-one; mp.157.5° C.

EXAMPLE XXXI

To a stirred and refluxing mixture of 23.4 parts of (4-chlorophenyl)(2-fluorophenyl)methanone in 280 parts of 2-propanol are addedportionwise 3.7 parts of sodium borohydride. Upon completion, stirringis continued for 2 hours at reflux temperature (±80° C.). The reactionmixture is cooled and decomposed by the addition of water. The2-propanol is evaporated and the residual product is extracted withtrichloromethane. The extract is dried, filtered and evaporated,yielding 4-chloro-α-(2-fluorophenyl)benzenemethanol as a residue.

To a stirred mixture of 23.6 parts of4-chloro-α-(2-fluorophenyl)benzenemethanol in 108 parts of benzene areadded dropwise 24 parts of sulfinyl chloride. Upon completion, the wholeis heated to reflux and stirring is continued first for 5 hours atreflux temperature and further overnight at room temperature. Thebenzene is evaporated and the residue is distilled, yielding1-chloro-4-[α-chloro-α-(2-fluorophenyl)methyl]benzene; bp. 122°-125° C.at 0.1 mm. pressure.

To a stirred and heated (95° C.) mixture of 202 parts of piperazine and720 parts of methylbenzene is added a solution of 120 parts of1-chloro-4-[α-chloro-α-(2-fluorophenyl)methyl]benzene in 180 parts ofmethylbenzene. The whole is stirred first for 1.50 hours at atemperature below 105° C. with water-separator and further for 24 hoursat 100° C. The reaction mixture is allowed to cool to room temperature,washed with water, dried, filtered and evaporated. The residue isdistilled (bp. 90° C. at 0.2 mm. pressure). The distillate iscrystallized from petroleumether. The product is filtered off, yieldinga first fraction of1-[α-(4-chlorophenyl)-α-(2-fluorophenyl)methyl]piperazine. A secondfraction is allowed to crystallize from the filtrate, yielding1-[α-(4-chlorophenyl)-α-(2-fluorophenyl)methyl]piperazine.

EXAMPLE XXXII

A mixture of 21.5 parts of ethyl 4-hydroxy-1-piperidinecarboxylate, 35.2parts of bis(4-fluorophenyl)bromomethane and 8.6 parts of potassiumcarbonate is stirred and heated in an oil-bath at 140° C. for 3 hours.The reaction mixture is allowed to cool to room temperature and water isadded. The product is extracted with methylbenzene. The extract iswashed successively with water, a diluted hydrochloric acid solution anda sodium bicarbonate solution, dried, filtered and evaporated. Theforerun is distilled off (bp. till 143° C. at 0.5-1 mm. pressure),yielding ethyl 4-[bis(4-fluorophenyl)methoxy]-1-piperidinecarboxylate asan oily residue.

A mixture of 29 parts of ethyl4-[bis(4-fluorophenyl)methoxy]-1-piperidinecarboxylate, 25 parts ofpotassium hydroxide, 1 part of water and 160 parts of 2-propanol isstirred and refluxed for 4 hours. The solvent is evaporated and water isadded to the residue. The product is extracted with methylbenzene. Theextract is washed a few times with water, dried, filtered andevaporated. The oily residue is converted into the hydrochloride salt in4-methyl-2-pentanone and 2-propanol at room temperature. The salt isfiltered off and dried, yielding4-[bis(4-fluorophenyl)methoxy]piperidine hydrochloride; mp. 161.8° C.

EXAMPLE XXXIII

A mixture of 17.3 parts of 1-(ethoxycarbonyl)-4-hydroxypiperidine, 24.7parts of bromodiphenylmethane and 7 parts of potassium carbonate isstirred and heated in an oil-bath for 3 hours at 140° C. The reactionmixture is cooled, water is added and the product is extracted withmethylbenzene. The extract is washed a few times with water, dried,filtered and evaporated. The oily residue is distilled, yielding ethyl4-(diphenylmethoxy)-1-piperidinecarboxylate; bp. 150° C. at 0.4 mm.pressure.

A mixture of 24 parts of ethyl4-(diphenylmethoxy)-1-piperidinecarboxylate, 20 parts of potassiumhydroxide and 120 parts of 2-propanol is stirred and refluxed for 4hours. The 2-propanol is evaporated. Water is added to the residue andthe product is extracted with methylbenzene. The extract is washed threetimes with water, dried, filtered and evaporated. The oily residue isconverted into the hydrochloride salt in 2-propanone and 2-propanol. Thesalt is filtered off and dried, yielding 4-(diphenylmethoxy)piperidinehydrochloride; mp. 209.8° C.

EXAMPLE XXXIV

To a stirred mixture of 20 parts of aluminium chloride and 100 parts offluorobenzene are added dropwise 20.5 parts of 2,4-dichlorobenzoylchloride. Upon completion, the mixture is heated to reflux and stirredat reflux temperature for 5 minutes. The reaction mixture is poured ontocrushed ice and the product is extracted with 1,1'-oxybisethane. Theextract is dried and evaporated, yielding 30 parts of(2,4-dichlorophenyl)(4-fluorophenyl) methanone as an oily residue.

EXAMPLE XXXV

Following the procedure of Example XXXIV there is prepared(4-fluorophenyl)(4-pyridinyl)methanone; mp. 85.5° C., by the reaction of4-pyridinecarbonyl chloride hydrochloride with fluorobenzene.

EXAMPLE XXXVI

To a stirred and cooled (10°-15° C.) mixture of 25 parts of(2,4-dichlorophenyl)(4-fluorophenyl)methanone and 80 parts of methanolare added portionwise 4.9 parts of sodium borohydride at about 10° C.Upon completion, stirring is continued overnight at room temperature.The reaction mixture is diluted with water and the solvent isevaporated. The residue is taken up in water and the product isextracted with trichloromethane. The extract is washed with water,dried, filtered and evaporated, yielding 22 parts of2,4-dichloro-α-(4-fluorophenyl)benzenemethanol as a residue.

EXAMPLE XXXVII

Following the procedure of Example XXXVI and using an equivalent amountof an appropriate diarylmethanone as a starting material there areprepared:

α-(4-fluorophenyl)-4-pyridinemethanol; mp. 138.2° C.;

α-(4-fluorophenyl)-3-pyridinemethanol hydrochloride; mp. 158.3° C.; and

4-methoxy-α-[3-(trifluoromethyl)phenyl]benzenemethanol as a residue.

EXAMPLE XXXVIII

A mixture of 22 parts of 2,4-dichloro-α-(4-fluorophenyl)benzenemethanoland 240 parts of hydrochloric acid solution 12 N is stirred for 40 hoursat room temperature. The reaction mixture is poured onto ice-water andthe product is extracted with trichloromethane. The extract is washedwith water, dried, filtered and evaporated. The residue is distilled,yielding 13.2 parts of2,4-dichloro-1-[chloro-(4-fluorophenyl)methyl]benzene; bp. 146° C. at0.15 mm. pressure.

EXAMPLE XXXIX

Following the procedure of Example XXXVIII and using an equivalentamount of an appropriate diarylmethanol as a starting material there areprepared:

1-[α-chloro-α-(4-methoxyphenyl)methyl]-3-(trifluoromethyl)benzene as aresidue; and

1-[chloro-(4-methylphenyl)methyl]-4-fluorobenzene as a residue.

EXAMPLE XL

To a stirred mixture of 59 parts ofα-(4-fluorophenyl)-3-pyridinemethanol hydrochloride in 150 parts oftrichloromethane are added slowly 59.5 parts of sulfinyl chloride.Stirring is continued for 2 hours at reflux temperature. The reactionmixture is evaporated, yielding 64 parts (100%) of3-[α-chloro-α-(4-fluorophenyl)methyl]pyridine hydrochloride as an oilyresidue.

EXAMPLE XLI

Following the procedure of Example XL and using an equivalent amount ofan appropriate diarylmethanol as a starting material, there areprepared:

3-[α-chloro-α-(4-chlorophenyl)methyl]pyridine hydrochloride as aresidue;

4-[α-chloro-α-(4-fluorophenyl)methyl]pyridine hydrochloride; mp.198°-200° C.;

1-(chlorophenylmethyl)-2,3-dimethylbenzene; bp. 137° C. at 0.7 mm.pressure;

1-(chlorophenylmethyl)-2,4-dimethylbenzene; bp. 137° C. at 0.7 mm.pressure;

2-(chlorophenylmethyl)-1,4-dimethylbenzene; bp. 136° C. at 0.7 mm.pressure; and

1-(chlorophenylmethyl)-2-fluorobenzene; bp. 108°-109° C. at 0.4 mm.pressure.

EXAMPLE XLII

A mixture of 121 parts of piperazine, 54 parts of3-[α-chloro-α-(4-chlorophenyl)methyl]pyridine hydrochloride and 315parts of N,N-dimethylformamide is stirred for 20 hours at roomtemperature. The reaction mixture is evaporated and 250 parts of waterare added to the residue. The product is extracted with methylbenzene.The organic phase is washed with water and extracted with an acetic acidsolution 10%. The acid aqueous phase is alkalized with a sodiumhydroxide solution 60% and the product is extracted again withmethylbenzene. The extract is dried, filtered and evaporated. The oilyresidue is converted into the nitrate salt in ethanol. The salt isfiltered off, washed with ethanol and with 2,2'-oxybispropane andcrystallized from ethanol, yielding 48 parts of1-[α-(4-chlorophenyl)-α-(3-pyridinyl)methyl]piperazine trinitrate; mp.132.9° C.

EXAMPLE XLIII

Following the procedure of Example XLII and using equivalent amounts ofthe appropriate starting materials, there are prepared:

1-[α-(4-fluorophenyl)-α-(4-pyridinyl)methyl]piperazine; mp. 108.4° C.;

1-[(2-chlorophenyl)(3-chlorophenyl)methyl]piperazine;

1-[(2-fluorophenyl)phenylmethyl]piperazine ethanedioate (1:1); mp.195.5° C.;

1-[(4-fluorophenyl)-(4-methoxyphenyl)methyl]piperazine ethanedioate(1:2); mp. 280.1° C.; and

1-[(4-nitrophenyl)phenylmethyl]piperazine dihydrochloride.

EXAMPLE XLIV

A mixture of 5.3 parts of1-(3-chloropropyl)-1,3-dihydro-2H-benzimidazol-2-one, 5 parts of1-(diphenylmethyl)piperazine, 6.4 parts of sodium carbonate and 200parts of 4-methyl-2-pentanone is stirred and refluxed overnight withwater-separator. After cooling, water is added and the layers areseparated. The 4-methyl-2-pentanone-phase is dried, filtered andevaporated. The residue is purified by column-chromatography over silicagel using a mixture of trichloromethane and 5% of methanol as eluent.The pure fractions are collected and the eluent is evaporated. The oilyresidue is crystallized from a mixture of 2,2'-oxybispropane and a smallamount of 2-propanol. The product is filtered off and dried, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 153.6° C.

EXAMPLE XLV

Following the procedure of Example XLIV and using equivalent amounts ofrespectively an appropriate1-(chloroalkyl)-1,3-dihydro-2H-benzimidazol-2-one and an appropriate1-(diarylmethyl)piperazine as starting materials, the followingcompounds are obtained:

5-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 175° C.;

6-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 206.1° C.;

1-[2-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}ethyl]-1,3-dihydro-2H-benzimidazol-2-one,hemihydrate; mp. 132° C.

1-[2-{4-[α-(4-fluoropheyl)-α-phenylmethyl]-1-piperazinyl}ethyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 172.4° C.; and

1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-1,3-dihydro-5-methyl-2H-benzimidazol-2-one;mp. 214.6° C.

EXAMPLE XLVI

A mixture of 42.6 parts of1-(3-chloropropyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one,38 parts of 1-(diphenylmethyl)piperazine, 48 parts of sodium carbonateand 400 parts of 4-methyl-2-pentanone is stirred and refluxed overnightwith water-separator. The reaction mixture is cooled, water is cooledand the layers are separated. The 4-methyl-2-pentanone-phase is washedwith water, dried, filtered and evaporated. The oily residue is purifiedby column-chromatography over silica gel using a mixture oftrichloromethane and 5% of methanol as eluent. The pure fractions arecollected and the eluent is evaporated, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas a residue.

EXAMPLE XLVII

By repeating the procedure of Example XLVI and using an equivalentamount of an appropriately substituted1-(3-chloropropyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazole as astarting material, there are prepared:

1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-5-methyl-3-(1-methylethenyl)-2H-benzimidazol-2-oneas an oily residue; and

3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-5-methyl-1-(1-methylethenyl)-2H-benzimidazol-2-oneas an oily residue.

EXAMPLE XLVIII

A mixture of 4.5 parts of1-(2-chloroethyl)-2,3-dihydro-1H-benzimidazol-2-one, 5 parts of1-(diphenylmethyl)piperazine, 6.4 parts of sodium carbonate and 200parts of 4-methyl-2-pentanone is stirred and refluxed overnight withwater-separator. The reaction mixture is cooled and water is added. Theprecipitated product is filtered off and crystallized from a mixture ofN,N-dimethylformamide and water, yielding1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 218° C.

EXAMPLE IL

A mixture of 2.7 parts of1,3-dihydro-1-(3-hydroxypropyl)-2H-benzimidazol-2-one methanesulfonate,2.88 parts of 1-[bis(p-fluorophenyl)methyl]piperazine, 2.66 parts ofsodium carbonate and 100 parts of 4-methyl-2-pentanone is stirred andrefluxed overnight. After cooling, water is added and the layers areseparated. The organic phase is dried, filtered and evaporated. Theresidue is purified by column-chromatography over silica gel using amixture of trichloromethane and 5% of methanol as eluent. The purefractions are collected and the eluent is evaporated. The residue iscrystallized from 2-propanol, yielding1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 197.3° C.

EXAMPLE L

A mixture of 4.6 parts of1-(3-chlorophenyl)-1,3-dihydro-2H-benzimidazol-2-one, 5.4 parts of1-(p-fluoro-α-phenylbenzyl)piperazine, 15 parts of sodium carbonate, 0.2parts of potassium iodide and 80 parts of 4-methyl-2-pentanone isstirred and refluxed overnight. After cooling, water is added and thelayers are separated. The organic phase is dried, filtered andevaporated. The residue is boiled in 2,2'-oxybispropane with activatedcharcoal. The latter is filtered off and the product is allowed tocrystallize from the filtrate while stirring. It is filtered off andcrystallized from 4-methyl-2-pentanone, yielding1-[3-{4-[α-(4-fluorophenyl)-α-phenylmethyl]-1-piparazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 153.6° C.

EXAMPLE LI

Following the procedure of Example L and using equivalent amounts of theappropriate starting materials, the following compounds are prepared:

1-[3-{4-[α-(4-chlorophenyl)-α-phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 180.2° C.;

1-[3-{4-[α-(4-chlorophenyl)-α-(2-fluorophenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 136° C.;

1-[3-{4[bis(4-fluorophenyl)methyl]-1-piperazinyl}propyl]-5-chloro-1,3-dihydro-2H-benzimidazol-2-one;mp. 205.8° C.;

1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}propyl]-6-chloro-1,3-dihydro-2H-benzimidazol-2-onehydrate; mp. 132.9° C.;

1-{4-[4-(diphenylmethyl)-1-piperazinyl]butyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 196.6° C.;

6-chloro-1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 204.1° C.;

5-chloro-1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 203.6° C.; and

1-{4-[4-(diphenylmethyl)-1-piperazinyl]butyl}-1,3-dihydro-2H-benzimidazol-2-onehemihydrate; mp. 197.8° C.

EXAMPLE LII

A mixture of 6 parts of1-(3-chlorophenyl)-1,3-dihydro-3-(phenylmethyl)-2H-benzimidazol-2-one,4.5 parts of 1-(diphenylmethyl)piperazine, 5.3 parts of sodiumcarbonate, 0.1 parts of potassium iodide and 200 parts of4-methyl-2-pentanone is stirred and refluxed for 20 hours withwater-separator. The reaction mixture is cooled, water is added and thelayers are separated. The organic phase is dried, filtered andevaporated. The residue is converted into the hydrochloride salt in2,2'-oxybispropane and 2-propanol. The salt is filtered off andcrystallized from 2-propanone, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-3-(phenylmethyl)-2H-benzimidazol-2-onedihydrochloride; mp. 199.6° C.

EXAMPLE LIII

A mixture of 4.94 parts of1-(4-chlorobutyl)-1,3-dihydro-2H-benzimidazol-2-one, 5.76 parts of1-[bis(4-fluorophenyl)methyl]piperazine, 5.3 parts of sodium carbonate,0.2 parts of potassium iodide and 200 parts of 4-methyl-2-pentanone isstirred and refluxed for 20 hours with water-separator. The reactionmixture is cooled, water is added and the layers are separated. Theorganic phase is dried, filtered and evaporated. The residue iscrystallized from ethanol. The product is filtered off and dried,yielding1-[4-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}butyl]-1,3-dihydro-2H-benzimidazol-2-onedihydrochloride. hydrate; mp. 184.4° C.

EXAMPLE LIV

A mixture of 12 parts of1-(3-chloro-2-methylpropyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one,5.76 parts of 1-[bis(4-fluorophenyl)methyl]piperazine, 5.3 parts ofsodium carbonate, 0.2 parts of potassium iodide and 200 parts of4-methyl-2-pentanone is stirred and refluxed for 20 hours withwater-separator. The reaction mixture is cooled, water is added and thelayers are separated. The organic phase is dried, filtered andevaporated, yielding1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}-2-methylpropyl]-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas an oily residue.

EXAMPLE LV

Following the procedure of Example LIV and using equivalent amounts ofthe appropriate starting materials, there are prepared:

1-[3-{4-[(4-chlorophenyl)(3-pyridinyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas a residue;

1-[3-{4-[(4-fluorophenyl)(4-pyridinyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas a residue;

1-[3-{4-[(4-chlorophenyl)(4-methoxyphenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas a residue;

1,3-dihydro-1-[3-{4-[(4-nitrophenyl)phenylmethyl]-1-piperazinyl}propyl]-2H-benzimidazol-2-one;mp. 103.6° C.;

1-[3-{4-[(2-fluorophenyl)phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-oneas a residue;

1-[3-{4-[(4-fluorophenyl)(4-methoxyphenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 157.4° C.; and

1-[3-{4-[(4-bromophenyl)phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 189.7° C.

EXAMPLE LVI

A mixture of 4.94 parts of1-(4-chlorobutyl)-1,3-dihydro-2H-benzimidazol-2-one, 5.76 parts of1-[bis(4-fluorophenyl)methyl]piperazine, 5.3 parts of sodium carbonate,0.1 parts of potassium iodide and 200 parts of 4-methyl-2-pentanone isstirred and refluxed for 20 hours with water-separator. After cooling,water is added and the layers are separated. The organic phase is dried,filtered and evaporated. The residue is crystallized from ethanol. Theproduct is filtered off and dried, yielding1-[4-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}butyl]-1,3-dihydro-2H-benzimidazol-2-onedihydrochloride. hydrate. hemiethanolate; mp. 172.9° C.

EXAMPLE LVII

A mixture of 5.5 parts of1,3-dihydro-1-(3-iodopropyl)-3-methyl-2H-benzimidazol-2-one, 3.8 partsof 1-(diphenylmethyl)piperazine, 4 parts of sodium carbonate and 200parts of 4-methyl-2-pentanone is stirred and refluxed for 5 hours. Thereaction mixture is cooled to room temperature and water is added. Theorganic phase is separated, dried, filtered and evaporated. The residueis purified by column-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5) as eluent. The pure fractions arecollected and the eluent is evaporated. The residue is converted intothe hydrochloride salt in 2-propanol and 1,1'-oxybisethane. The salt isfiltered off and crystallized from ethanol, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-3-methyl-2H-benzimidazol-2-onedihydrochloride. hydrate; mp. 201.8° C.

EXAMPLE LVIII

A mixture of 4.2 parts of1-(3-chloropropyl)-1,3-dihydro-2H-benzimidazol-2-one, 5.7 parts of1-[α-(3-chlorophenyl)-α-phenylmethyl]piperazine, 4.75 parts of sodiumcarbonate, 0.1 parts of potassium iodide and 200 parts of4-methyl-2-pentanone is stirred and refluxed overnight. After cooling,water is added and the layers are separated. The organic phase is dried,filtered and evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5 by volume) as eluent. The purefractions are collected and the eluent is evaporated. The residue iscrystallized from a mixture of 4-methyl-2-pentanone and2,2'-oxybispropane. The product is filtered off and recrystallized from4-methyl-2-pentanone, yielding1-[3-{4-[α-(3-chlorophenyl)-α-phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 112.7° C.

EXAMPLE LIX

Following the procedure of Example LVIII and using equivalent amounts ofthe appropriate starting materials, the following compounds are preparedin free base form or in the form of a hydrochloride salt after treatmentof the base with hydrochloric acid in ethanol.

4-chloro-3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 196.9° C.; and

5-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-3-phenyl-2H-benzimidazol-2-onedihydrochloride. hemihydrate; mp. 184.2° C.

EXAMPLE LX

A mixture of 5.4 parts of 3-(3-bromopropyl)-2(3H)-benzothiazolone, 4.5parts of 1-(diphenylmethyl)piperazine, 5.3 parts of sodium carbonate,0.1 parts of potassium iodide and 200 parts of 4-methyl-2-pentanone isstirred and refluxed for 4 hours with water-separator. After cooling,water is added and the layers are separated. The organic phase is dried,filtered and evaporated. The residue is converted into the hydrochloridesalt in 2,2'-oxybispropane and 2-propanol. The salt is filtered off andcrystallized from ethanol, yielding3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2(3H)-benzothiazolonedihydrochloride.hemihydrate; mp. 186.1° C.

EXAMPLE LXI

A mixture of 4.9 parts of 3-(3-chloropropyl)-2(3H)-benzoxazolone, 5parts of 1-(diphenylmethyl)piperazine, 6.4 parts of sodium carbonate and200 parts of 4-methyl-2-pentanone is stirred and refluxed overnight withwater-separator. The reaction mixture is cooled, water is added and thelayers are separated. The 4-methyl-2-pentanone phase is dried, filteredand evaporated. The oily residue is dissolved in 2,2'-oxybispropane andthe solution is stirred with activated charcoal. The latter is filteredoff over hyflo and the clear filtrate is acidified with 2-propanol,previously saturated with gaseous hydrogen chloride. The formedhydrochloride salt is filtered off and triturated in 2-propanol. It isfiltered off again and dried, yielding3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2(3H)benzoxazolonedihydrochloride; mp. 212.4° C.

EXAMPLE LXII

A mixture of 4.9 parts of 1-(3-chloropropyl)-1H-benzimidazole, 5.76parts of 1-[bis(4-fluorophenyl)methyl]piperazine, 5.3 parts of sodiumcarbonate, 0.1 parts of potassium iodide and 200 parts of4-methyl-2-pentanone is stirred and refluxed for 20 hours withwater-separator. The reaction mixture is cooled, water is added and thelayers are separated. The organic phase is dried, filtered andevaporated. The residue is crystallized from a mixture of4-methyl-2-pentanone and 2,2'-oxybispropane. The product is filtered offand dried, yielding1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}propyl]-1H-benzimidazolehydrate; mp. 108.4° C.

EXAMPLE LXIII

Following the procedure of Example LXII and using equivalent amounts ofthe appropriate starting materials, the following compounds are obtainedin free base form or in the form of a hydrochloride salt after treatmentof the base with hydrochloric acid.

1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-1H-benzimidazole; mp.192.3° C.;

1-[3-{4-[(3-chlorophenyl)phenylmethyl]-1-piperazinyl}propyl]-1H-benzimidazoletrihydrochloride.hydrate.hemi-2-propanolate; mp. 191.1° C.;

1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-phenyl-1H-benzimidazole;mp. 130.5° C.;

6-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-phenyl-1H-benzimidazole;mp. 143.9° C.;

1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-2-phenyl-1H-benzimidazoletrihydrochloride.hydrate; mp. 198.3° C.;

5-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-phenyl-1H-benzimidazole;mp. 127.8° C.;

1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-(phenylmethyl)-1H-benzimidazoletrihydrochloride.trihydrate; mp. 179.9° C.; and

5-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-(phenylmethyl)-1H-benzimidazoletrihydrochloride.hydrate; mp. 198.2° C.

EXAMPLE LXIV

A mixture of 4.5 parts of 1-(3-chloropropyl)-1H-benzimidazole, 5.1 partsof 1-(diphenylmethyl)piperazine, 3.7 parts of sodium carbonate, 0.1parts of potassium iodide and 80 parts of 4-methyl-2-pentanone isstirred and refluxed overnight. The reaction mixture is cooled, water isadded and the layers are separated. The organic phase is dried, filteredand evaporated. The residue is purified by column-chromatography oversilica gel using a mixture of trichloromethane and methanol (95:5 byvolume) as eluent. The pure fractions are collected and the eluent isevaporated. The residue is crystallized from a mixture of4-methyl-2-pentanone and 2,2'-oxybispropane, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazole; mp.132.3° C.

EXAMPLE LXV

Following the procedure of Example LXIV and using equivalent amounts ofthe appropriate starting materials, the following compounds are preparedin free base form or in the form of a hydrochloride salt after treatmentof the base with hydrochloric acid.

1-[3-{4-[(4-fluorophenyl)phenylmethyl]-1-piperazinyl}propyl]-1H-benzimidazole;mp. 102.5° C.;

1-[3-{4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl}propyl]-1H-benzimidazole;mp. 90.8° C.;

1-{4-[4-(diphenylmethyl)-1-piperazinyl]butyl}-1H-benzimidazole; mp. 106°C.;

1-[4-{4-[(4-fluorophenyl)phenylmethyl]-1-piperazinyl}butyl]-1H-benzimidazole;mp. 114.9° C.;

1-[4-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}butyl]-1H-benzimidazole;mp. 86.3° C.;

1-{3-[4-(diphenylmethyl)-1-piperazinyl]-2-methylpropyl}-1H-benzimidazoletrihydrochloride.hemihydrate; mp. 237.3° C.;

1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}-2-methylpropyl]-1H-benzimidazoletrihydrochloride.hemihydrate; mp. 223.4° C.;

1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-methyl-1H-benzimidazole;mp. 121.2° C.;

5-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-methyl-1H-benzimidazoletrihydrochloride.hydrate; mp. 226.4° C.;

1-{4-[4-(diphenylmethyl)-1-piperazinyl]butyl}-2-methyl-1H-benzimidazole;mp. 118.7° C.;

1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-2-ethyl-1H-benzimidazoletrihydrochloride.hydrate; mp. 208.5° C.;

1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-ethyl-1H-benzimidazoletrihydrochloride.hydrate; mp. 224.5° C.;

5-chloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-ethyl-1H-benzimidazoletrihydrochloride.hydrate; mp. 233.1° C.;

2-cyclohexyl-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazole;mp. 106.5° C.;

5-chloro-2-cyclohexyl-1-{3-[4-diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazole;mp. 114.9° C.; and

6-chloro-2-cyclohexyl-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazole;mp. 173.6° C.

EXAMPLE LXVI

A mixture of 4.9 parts of 1-(3-chloropropyl)-1H-benzimidazole, 7 partsof 1-[(2-chlorophenyl)phenylmethyl]piperazine acetate, 10.6 parts ofsodium carbonate, 0.1 parts of potassium iodide and 200 parts of4-methyl-2-pentanone is stirred and refluxed for 20 hours withwater-separator. The reaction mixture is cooled, water is added and thelayers are separated. The organic phase is dried, filtered andevaporated. The residue is converted into the hydrochloride salt in2-propanol and 2,2'-oxybispropane. The salt is filtered off andcrystallized from 2-propanol, yielding1-[3-{4-[(2-chlorophenyl)phenylmethyl]-1-piperazinyl}propyl]-1H-benzimidazoletrihydrochloride dihydrate; mp. 182.9° C.

EXAMPLE LXVII

A mixture of 6 parts of 3-[2-(methylthio)-1H-benzimidazol-1-yl]propylmethanesulfonate, 3.78 parts of 1-(diphenylmethyl)piperazine, 5.3 partsof sodium carbonate and 200 parts of 4-methyl-2-pentanone is stirred andrefluxed for 5 hours with water-separator. After cooling, water is addedand the layers are separated. The organic phase is dried, filtered andevaporated. The residue is converted into the hydrochloride salt in2,2'-oxybispropane and 2-propanol. The salt is filtered off andcrystallized from ethanol, yielding, after drying,1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2-(methylthio)-1H-benzimidazoletrihydrochloride.hydrate; mp. 203.4° C.

EXAMPLE LXVIII

A mixture of 6.95 parts of1-(5-chloropentyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one,5.15 parts of 1-(diphenylmethyl)piperazine, 5.30 parts of sodiumcarbonate, 0.1 parts of potassium iodide and 160 parts of4-methyl-2-pentanone is stirred and refluxed overnight withwater-separator. The reaction mixture is cooled to room temperature,water is added and the layers are separated. The organic phase is dried,filtered and evaporated. The residue is stirred and refluxed for 30minutes with 12 parts of a hydrochloric acid solution in 40 parts ofethanol. The whole is evaporated and the residue is crystallized fromethanol, yielding1-{5-[4-(diphenylmethyl)-1-piperazinyl]pentyl}-1,3-dihydro-2H-benzimidazol-2-onedihydrochloride.hydrate; mp. 215.3° C.

EXAMPLE LXIX

A mixture of 6.95 parts of1-(5-chloropentyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one,5.7 parts of 1-[bis(4-fluorophenyl)methyl]piperazine, 5.3 parts ofsodium carbonate, 0.1 parts of potassium iodide and 160 parts of4-methyl-2-pentanone is stirred and refluxed overnight. The reactionmixture is cooled to room temperature, water is added and the layers areseparated. The organic phase is dried, filtered and evaporated. Theresidue is stirred and refluxed for 30 minutes with a solution of 12parts of a concentrated hydrochloric acid solution in 40 parts ofethanol. The solvent is evaporated and the free base is liberated in theconventional manner with a diluted ammonium hydroxide solution. Theproduct is extracted with trichloromethane. The extract is dried,filtered and evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (90:10 by volume) as eluent. The purefractions are collected and the eluent is evaporated. The residue isconverted into the hydrochloride salt in ethanol and 2-propanol. Thesalt is filtered off and dried, yielding1-[5-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}pentyl]-1,3-dihydro-2H-benzimidazol-2-onedihydrochloride.hydrate; mp. 203.7° C.

EXAMPLE LXX

Following the procedure of Example LXIX and using equivalent amounts ofthe appropriate starting materials, there are prepared:

1-[4-{4-[(4-fluorophenyl)phenylmethyl]-1-piperazinyl}-butyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 172.3° C.;

1-[3-{4-[(2-chlorophenyl)phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 149° C.;

1-[3-{4-[(2-chlorophenyl)(3-chlorophenyl)methyl]-1-piperazinyl}propyl-1,3-dihydro-2H-benzimidazol-2-onehydrate; mp. 139.1° C.; and

1-[3-{4-[(2,4-dichlorophenyl)phenylmethyl]-1-piperazinyl}-propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 160.1° C.

EXAMPLE LXXI

To a stirred solution of 76 parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-onein 280 parts of ethanol are added 120 parts of a hydrochloric acidsolution and 250 parts of water. The whole is stirred for 30 minutes atroom temperature. Upon cooling in an ice-bath, the product isprecipitated. It is filtered off, washed with 2-propanone and with2,2'-oxybispropane, and dried, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-onedihydrochloride.hydrate; mp. 237.5° C.

EXAMPLE LXXII

Following the procedure of Example LXXI and using equivalent amounts ofthe appropriate starting materials, there are prepared:

1-[3-{4-[(4-chlorophenyl)(3-pyridinyl)methyl]-1-piperazinyl}-propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 160.2° C.;

1-[3-{4-[(4-fluorophenyl)(4-pyridinyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 183.2° C.;

1-[3-{4-[(4-chlorophenyl)(4-methoxyphenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 199.3° C.; and

1-[3-{4-[(2-fluorophenyl)phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 157.7° C.

EXAMPLE LXXIII

A mixture of 7.3 parts of1-(6-chlorohexyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one,5.15 parts of 1-(diphenylmethyl)piperazine, 5.3 parts of sodiumcarbonate, 0.1 parts of potassium iodide and 160 parts of4-methyl-2-pentanone is stirred and refluxed overnight withwater-separator. The reaction mixture is cooled, water is added and thelayers are separated. The organic phase is dried, filtered andevaporated. The residue is stirred and refluxed for one hour with 12parts of a concentrated hydrochloric acid solution and 40 parts ofethanol. The solvent is evaporated and the residue is taken up in water.The free base is liberated in the conventional manner with ammoniumhydroxide. The product is extracted with trichloromethane. The extractis dried, filtered and evaporated. The residue is crystallized frommethanol. The product is filtered off and recrystallized fromN,N-dimethylformamide, yielding1-{6-[4-(diphenylmethyl)-1-piperazinyl]hexyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 189.7° C.

EXAMPLE LXXIV

A mixture of 3.65 parts of1-(6-chlorohexyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one,2.9 parts of 1-[bis(4-fluorophenyl)methyl]piperazine, 2.65 parts ofsodium carbonate, 0.1 parts of potassium iodide and 80 parts of4-methyl-2-pentanone is stirred and refluxed overnight. The reactionmixture is cooled, water is added and the layers are separated. Theorganic phase is dried, filtered and evaporated. The residue is stirredfor 30 minutes with a solution of 12 parts of a concentratedhydrochloric acid solution in 40 parts of ethanol. The solvent isevaporated and the residue is dissolved in water. The free base isliberated in the conventional manner with ammonium hydroxide andextracted with trichloromethane. The extract is dried, filtered andevaporated. The residue is converted into the hydrochloride salt inethanol and 2-propanol. The salt is filtered off and dried, yielding1-[6-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}hexyl]-1,3-dihydro-2H-benzimidazol-2-onedihydrochloride; mp. 204.5° C.

EXAMPLE LXXV

A mixture of 9.6 parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-5-methyl-3-(1-methylethenyl)-2H-benzimidazol-2-one,24 parts of a hydrochloric acid solution, 50 parts of water and 96 partsof ethanol is stirred first for a while at about 50° C. and further for30 minutes at room temperature. The reaction mixture is evaporated andthe oily residue is triturated in 2-propanone. The hydrochloride salt isfiltered off and the free base is liberated in the conventional mannerwith ammonium hydroxide in water. The product is extracted withmethylbenzene. The extract is dried, filtered and evaporated. Thesemi-solid residue is crystallized from a mixture of 2-propanol and2,2'-oxybispropane. The product is filtered off and dried, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-5-methyl-2H-benzimidazol-2-one;mp. 178.3° C.

EXAMPLE LXXVI

To a stirred solution of 9.6 parts of3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-5-methyl-1-(1-methylethenyl)-2H-benzimidazol-2-onein 80 parts of ethanol are added 24 parts of a concentrated hydrochloricacid solution and 50 parts of water (exothermic reaction: temperaturerises to 50° C.). Stirring is continued for 30 minutes at roomtemperature. The reaction mixture is evaporated and the residue istriturated in 2-propanone. The hydrochloride salt is filtered off andthe free base is liberated in the conventional manner with ammoniumhydroxide. Methylbenzene is added and the precipitated free base isfiltered off. It is crystallized from a mixture of 2-propanol and asmall amount of N,N-dimethylformamide, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-6-methyl-2H-benzimidazol-2-one;mp. 195.7° C.

EXAMPLE LXXVII

A stirred solution of 8 parts of1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}-2-methylpropyl]-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-onein 120 parts of ethanol is acidified with 2-propanol, previouslysaturated with gaseous hydrogen chloride. The whole is stirred andrefluxed for 5 minutes. The reaction mixture is evaporated. The residueis taken up in water and the whole is alkalized with a concentratedammonium hydroxide solution. The oily product is extracted withtrichloromethane. The extract is dried, filtered and evaporated. Theresidue is crystallized from 4-methyl-2-pentanone. The product isfiltered off and dried, yielding1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}-2-methylpropyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 176° C.

EXAMPLE LXXVIII

A mixture of 3.6 parts of N¹-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-4-(trifluoromethyl-1,2-benzendiamineand 1.8 parts of urea is stirred for 3 hours in an oil-bath at 190° C.The reaction mixture is cooled, water and trichloromethane are added andthe layers are separated. The organic phase is dried, filtered andevaporated. The residue is purified by column-chromatography over silicagel using a mixture of trichloromethane and methanol (95:5 by volume) aseluent. The pure fractions are collected and the eluent is evaporated,yielding1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-1,3-dihydro-5-(trifluoromethyl)-2H-benzimidazol-2-one;mp. 163.7° C.

EXAMPLE LXXIX

A mixture of 5.4 parts of urea and 13.7 parts of N¹-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-4-(trifluoromethyl)-1,2-benzenediamineis stirred and heated for 4 hours at 190° C. The reaction mixture iscooled to room temperature and diluted with water. After the addition oftrichloromethane, the layers are separated. The aqueous phase isextracted with trichloromethane. The combined organic phases are washedwith water, dried, filtered and evaporated. The oily residue is purifiedby column-chromatography over silica gel using trichloromethane andmethanol (90:10 by volume) as eluent. The pure fractions are collectedand the eluent is evaporated. The residue is crystallized from2,2'-oxybispropane. The product is filtered off and dried, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-5-(trifluoromethyl)-2H-benzimidazol-2-one;mp. 152.7° C.

EXAMPLE LXXX

A mixture of 4 parts of 4,5-dichloro-N¹-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,2-benzenediamine and 1.5parts of urea is stirred for 3 hours in an oil-bath at 190° C. Aftercooling, water and trichloromethane are added. The layers are separatedand the organic phase is dried, filtered and evaporated. The residue ispurified by column-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5 by volume) as eluent. The purefractions are collected and the eluent is evaporated. The residue iscrystallized from a mixture of methylbenzene and 2,2'-oxybispropane,yielding5,6-dichloro-1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 214.7° C.

EXAMPLE LXXXI

A mixture of 4.37 parts ofN-(2-aminophenyl)-4-(diphenylmethyl)-1-piperazinepropanaminehydrochloride, 38 parts of carbon disulfide, 2 parts of sodium carbonateand 40 parts of ethanol is stirred and refluxed for 20 hours. Thereaction mixture is evaporated and water is added to the residue. Theprecipitated product is filtered off, washed with water and dissolved intrichloromethane. The solution is dried, filtered and evaporated. Theresidue is crystallized from 4-methyl-2-pentanone, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazole-2-thiol;mp 181.8° C.

EXAMPLE LXXXII

A mixture of 60 parts ofN-(2-aminophenyl)-4-(diphenylmethyl)-1-piperazinepropanamine, 20 partsof methyl(iminomethoxymethyl)carbamate, 42 parts of acetic acid and 450parts of trichloromethane is stirred and refluxed overnight. Thereaction mixture is evaporated and the residue is stirred in water. Thelatter is decanted and the residue is taken up again in water. The wholeis alkalized with a diluted ammonium hydroxide solution and the productis extracted with trichloromethane. The extract is dried, filtered andevaporated. The residue is purified by column-chromatography over silicagel using a mixture of trichloromethane and methanol (95:5 by volume) aseluent. The pure fractions are collected and the eluent is evaporated.The residue is crystallized from a mixture of 4-methyl-2-pentanone and2,2'-oxybispropane, yielding methyl[1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazol-2-yl]carbamate;mp. 137.8° C.

A mixture of 12 parts of methyl[1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazol-2-yl]carbamate,60 parts of a concentrated hydrochloric acid solution and 80 parts ofethanol is stirred and refluxed overnight. The reaction mixture isevaporated and water is added to the residue. The free base is liberatedin the conventional manner with ammonium hydroxide and extracted withtrichloromethane. The extract is dried, filtered and evaporated. Theresidue is crystallized from ethanol. The product is filtered off anddried, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazol-2-amino;mp. 228.7° C.

A mixture of 10.7 parts of1-{3-[4-(diphenylmethyl)piperazinyl]propyl}-1H-benzimidazol-2-amine, 5.1parts of acetic acid anhydride and 90 parts of methylbenzene is stirredand refluxed for 5 hours. The reaction mixture is evaporated and theresidue is stirred in water. The whole is alkalized with ammoniumhydroxide and the product is extracted with trichloromethane. Theextract is dried, filtered and evaporated. The residue is crystallizedfrom ethanol. The product is filtered off and dried, yieldingN-[1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-ylidene]acetamide;mp. 143.3° C.

EXAMPLE LXXXIII

A mixture of 2.3 parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one,4.5 parts of formaldehyde solution 40% and 45 parts ofN,N-dimethylformamide is stirred and heated for 2 hours at 100° C. Thereaction mixture is cooled and diluted with water. The precipitatedproduct is filtered off and crystallized from methylbenzene, yielding,after drying,1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-3-(hydroxymethyl)-2H-benzimidazol-2-one;mp. 102.5° C.

EXAMPLE LXXXIV

A mixture of 1.55 parts of acetic acid anhydride, 3 parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-oneand 22.5 parts of methylbenzene is stirred and refluxed overnight. Wateris added to the reaction mixture and the layers are separated. Theorganic phase is dried, filtered and evaporated. The residue is purifiedby column-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5 by volume) as eluent. The purefractions are collected and the eluent is evaporated, yielding1-acetyl-3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 124.4° C.

EXAMPLE LXXXV

A mixture of 1.1 parts of ethyl 2-propenoate, 3 parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one,a few drops of a N,N,N-trimethylbenzenemethanaminium hydroxide solution40% in methanol and 25 parts of 1,4-dioxane is stirred and refluxed for24 hours. The reaction mixture is evaporated. The residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5 by volume) as eluent. The purefractions are collected and the eluent is evaporated. The residue isconverted into the hydrochloride salt in 2-propanol and ethanol. Thesalt is filtered off and dried, yielding ethyl3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2,3-dihydro-2-oxo-1H-benzimidazole-1-propanoatedihydrochloride. dihydrate; mp. 204° C.

EXAMPLE LXXXVI

A mixture of 3 parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one,1 part of isocyanatomethane and 25 parts of 1,4-dioxane is stirred andrefluxed overnight. The reaction mixture is evaporated and the residueis purified by column-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5 by volume) as eluent. The purefractions are collected and the eluent is evaporated. The residue iscrystallized from a mixture of methylbenzene and 2,2'-oxybispropane,yielding3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2,3-dihydro-N-methyl-2-oxo-1H-benzimidazole-1-carboxamide;mp. 153.1° C.

EXAMPLE LXXXVII

A mixture of 4.8 parts of1-(3-chloropropyl)-1,3-dihydro-2H-benzimidazol-2-one, 6.1 parts of4-(diphenylmethoxy)piperidine hydrochloride, 7.5 parts of sodiumcarbonate and 200 parts of 4-methyl-2-pentanone is stirred and refluxedovernight with water-separator. The reaction mixture is cooled and wateris added. The layers are separated and the 4-methyl-2-pentanone-phase isdried, filtered and evaporated. The oily residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and 5% of methanol as eluent. The pure fractions arecollected and the eluent is evaporated. The residue is crystallized from4-methyl-2-pentanone, yielding1-{3-[4-(diphenylmethoxy)-1-piperidinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 149.2° C.

EXAMPLE LXXXVIII

Following the procedure of Example LXXXVII and using equivalent amountsof the appropriate starting materials, the following compounds areobtained in free base form or in the form of a hydrochloride salt aftertreatment of the base with hydrochloric acid.

1-{2-[4-(diphenylmethoxy)-1-piperidinyl]ethyl}-1,3-dihydro-2H-benzimidazol-2-onehydrochloride; mp. 253.1° C.;

1-[3-{4-[bis(4-fluorophenyl)methoxy]-1-piperidinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-onehydrochloride. hemihydrate; mp. 167.2° C.;

1-[2-{4-[bis(4-fluorophenyl)methoxy]-1-piperidinyl}ethyl]-1,3-dihydro-2H-benzimidazol-2-onehydrochloride. hemihydrate; mp. 251.4° C.; and

1-{4-[4-(diphenylmethyl)-1-piperidinyl]butyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 152° C.

EXAMPLE LXXXIX

A mixture of 6 parts of 1-(3-chloropropyl)-1H-benzimidazole, 7.6 partsof 4-(diphenylmethoxy)piperidine hydrochloride, 10.6 parts of sodiumcarbonate and 200 parts of 4-methyl-2-pentanone is stirred and refluxedovernight with water-separator. The reaction mixture is cooled, water isadded and the layers are separated. The 4-methyl-2-pentanone-phase isdried, filtered and evaporated. The oily residue is purified bycolumn-chromatography over silica gel using a mixture oftrichloromethane and methanol (95:5 by volume) as eluent. The purefractions are collected and the eluent is evaporated. The oily residueis crystallized from 2,2'-oxybispropane. The product is filtered off anddried, yielding1-{3-[4-(diphenylmethoxy)-1-piperidinyl]propyl}-1H-benzimidazole; mp.110.2° C.

EXAMPLE XC

A mixture of 13 parts of1,3-dihydro-1-[3-(1-piperazinyl)propyl]-2H-benzimidazol-2-one, 12.4parts of 1,1'-(bromomethylene)bis[benzene], 6.6 parts of sodiumcarbonate and 200 parts of 4-methyl-2-pentanone is stirred and refluxedovernight with water-separator. After cooling to room temperature, wateris added and the layers are separated. The organic layer is dried,filtered and evaporated. The residue is crystallized from a mixture of2,2'-oxybispropane and a small amount of 2-propanol, yielding1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 153° C.

EXAMPLE XCI

Following the procedure of Example XC and using equivalent amounts ofthe appropriate starting materials, the following compounds areprepared:

1-[2-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}ethyl]-1,3-dihydro-2H-benzimidazol-2-onehemihydrate; mp. 131.5° C.;

1-{2-[4-(diphenylmethyl)-1-piperazinyl]ethyl}-1,3-dihydro-2H-benzimidazol-2-one;mp. 218° C.; and

1-[3-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 198° C.

EXAMPLE XCII

A mixture of 5.2 parts of1,3-dihydro-1-[3-(1-piperazinyl)propyl]-2H-benzimidazol-2-one, 5.28parts of 2-(chlorophenylmethyl)pyridine hydrochloride, 5.3 parts ofsodium carbonate and 90 parts of N,N-dimethylformamide is stirred andheated overnight at 50° C. The reaction mixture is cooled and pouredonto ice-water. The product is extracted with methylbenzene. The extractis dried, filtered and evaporated. The residue is crystallized from amixture of 4-methyl-2-pentanone and 2,2'-oxybispropane. The product isfiltered off and dried, yielding 2 parts (23.4%) of1,3-dihydro-1-[3-{4-[phenyl(2-pyridinyl)methyl]-1-piperazinyl}propyl]-2H-benzimidazol-2-one;mp. 141.7° C.

EXAMPLE XCIII

Following the procedure of Example XCII and using equivalent amounts ofthe appropriate starting materials, the following compounds areprepared:

1-[3-{4-[(4-fluorophenyl)(3-pyridinyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 154.1° C.;

1,3-dihydro-1-[3-{4-[phenyl(3-pyridinyl)methyl]-1-piperazinyl}propyl]-2H-benzimidazol-2-one;mp. 162.6° C.;

1-[3-{4-[(4-fluorophenyl)-(4-methylphenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 147.8° C.;

1-[3-{4-[bis(4-chlorophenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 209.5° C.;

1-[3-{4-[(2,4-dichlorophenyl)(4-fluorophenyl)methyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 160.1° C.;

1-[3-{4-[(2,3-dimethylphenyl)phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 169.8° C.;

1,3-dihydro-1-{3-[4-{(4-methoxyphenyl)[3-(trifluoromethyl)phenyl]methyl}-1-piperazinyl]-propyl}-2H-benzimidazol-2-one;mp. 153.4° C.;

1,3-dihydro-1-[3-{4-[(4-methylphenyl)phenylmethyl]-1-piperazinyl}propyl]-2H-benzimidazol-2-one;mp. 178.3° C.;

1-[3-{4-[(2,4-dimethylphenyl)phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 115.8° C.; and

1-[3-{4-[(2,5-dimethylphenyl)phenylmethyl]-1-piperazinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one;mp. 156.3° C.

EXAMPLE XCIV

50 Parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-oneare dissolved in 200 of 2-propanol while stirring and heating. Thesolution is stirred with 2.5 parts of activated charcoal. The latter isfiltered off and upon cooling to room temperature, the product iscrystallized. It is filtered off and converted into the hydrochloridesalt in 2-propanol. The salt is filtered off, washed twice with2-propanol and dried overnight in vacuo at 60° C. It is dissolved in 320parts of methanol and the free base is liberated in the conventionalmanner with a sodium hydroxide solution 5 N. The whole is concentratedto a volume of about 150 parts. The precipitated product is filteredoff, washed with 500 parts of water and dissolved in 120 parts of2-propanol. The solution is stirred and heated with 1 part of activatedcharcoal. The latter is filtered off over hyflo while hot. The filtrateis cooled to room temperature while stirring. The precipitated productis filtered off and dried over week-end in vacuo at 60° C., yielding21.49 parts of1{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-onehydrate; mp. 156.6° C.

EXAMPLE XCV

To a stirred mixture of 9.4 parts of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-oneand 180 parts of methylbenzene are added 0.8 parts of sodium hydridedispersion 75% and the whole is stirred and heated for 60 minutes at 90°C. After cooling to 30° C., 0.2 parts of2,3,11,12-dibenzo-1,4,7,10,13,16-hexaoxacyclooctadeca-2,11-diene areadded and stirring is continued for 10 minutes. Then there are added 4.2parts of ethyl 2-bromoacetate and the mixture is stirred and refluxedovernight. The reaction mixture is cooled to 90° C., 50 parts of waterare added and the layers are separated while hot. The organic phase isevaporated, yielding 10 parts of ethyl3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2,3-dihydro-2-oxo-1H-benzimidazole-1-acetateas a residue.

EXAMPLE XCVI

A mixture of 9.8 parts of ethyl 3-{3-[4-(diphenylmethyl)1-piperazinyl]propyl}-2,3-dihydro-2-oxo-1H-benzimidazole-1-acetate,1.2 parts of sodium hydroxide and 150 parts of water is stirred andrefluxed for 5 minutes (+80° C.). The reaction mixture is filtered andthe filtrate is acidified with acetic acid to pH 5.8-6: a stickyprecipitate is formed. It is separated and crystallized from ethanol andwater. The product is filtered off and dried in vacuo at 100° C. for 3hours, yielding 6 parts of3-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-2,3-dihydro-2-oxo-1H-benzimidazole-1-aceticacid hemihydrate; mp. 138.7° C.

We claim:
 1. A chemical compound selected from the group consisting of acompound having the formula ##STR66## and the pharmaceuticallyacceptable acid addition salts thereof, wherein: Ar¹ and Ar² are eachindependently selected from the group consisting of phenyl, substitutedphenyl and pyridinyl, wherein said substituted phenyl is phenyl havingfrom 1 to 2 substituents independently selected from the groupconsisting of halo, lower alkyl, lower alkyloxy, trifluoromethyl andnitro;n is an integer of from 2 to 6 inclusive, provided that when C_(n)H_(2n) represents a branched alkylene chain, then at least 2 carbonatoms are present in the linear portion of the chain linking B with thepiperazine nitrogen atom; and B is a radical having the formula##STR67## wherein: R¹ and R² are each independently selected from thegroup consisting of hydrogen, halo, lower alkyl and trifluoromethyl; andM is a member selected from the group consisting of phenyl,phenylmethyl, mercapto, lower alkylthio, amino, loweralkylcarbonylamino, lower alkyloxycarbonylamino, and cycloalkyl havingfrom 3 to 6 carbon atoms.
 2. A pharmaceutical composition comprising aninert carrier material and as an active ingredient an effectiveantihistaminic or anti-anaphylactic amount of a chemical compoundselected from the group consisting of a compound having the formula##STR68## and the pharmaceutically acceptable acid addition saltsthereof, wherein: Ar¹ and Ar² are each independently selected from thegroup consisting of phenyl, substituted phenyl and pyridinyl, whereinsaid substituted phenyl is phenyl having from 1 to 2 substituentsindependently selected from the group consisting of halo, lower alkyl,lower alkyloxy, trifluoromethyl and nitro;n is an integer of from 2 to 6inclusive, provided that when C_(n) H_(2n) represents a branchedalkylene chain, then at least 2 carbon atoms are present in the linearportion of the chain linking B with the piperazine nitrogen atom; and Bis a radical having the formula ##STR69## wherein: R¹ and R² are eachindependently selected from the group consisting of hydrogen, halo,lower alkyl, and trifluoromethyl; and M is a member selected from thegroup consisting of phenyl, phenylmethyl, mercapto, lower alkylthio,amino, lower alkylcarbonylamino, lower alkyloxycarbonylamino, andcycloalkyl having from 3 to 6 carbon atoms.
 3. A method of producingantihistaminic or anti-anaphylactic activity in a warm-blooded animal inneed of same which comprises systemic administration to saidwarm-blooded animal of an effective antihistaminic or anti-anaphylacticamount of a chemical compound selected from the group consisting of acompound having the formula ##STR70## and the pharmaceuticallyacceptable acid addition salts thereof, wherein: Ar¹ and Ar² are eachindependently selected from the group consisting of phenyl, substitutedphenyl and pyridinyl, wherein said substituted phenyl is phenyl havingfrom 1 to 2 substitutents independently selected from the groupconsisting of halo, lower alkyl, lower alkyloxy, trifluoromethyl andnitro;n is an integer of from 2 to 6 inclusive, provided that when C_(n)H_(2n) represents a branched alkylene chain, then at least 2 carbonatoms are present in the linear portion of the chain linking B with thepiperazine nitrogen atom; and B is a radical having the formula##STR71## wherein: R¹ and R² are each independently selected from thegroup consisting of hydrogen, halo, lower alkyl, and trifluoromethyl;and M is a member selected from the group consisting of hydrogen, loweralkyl, phenyl, phenylmethyl, mercapto, lower alkylthio, amino, loweralkylcarbonylamino, lower alkyloxycarbonylamino, and cycloalkyl havingfrom 3 to 6 carbon atoms.
 4. A method of producing antihistaminic oranti-anaphylactic activity in a warm-blooded animal in need of samewhich comprises systemic administration to said warm-blooded animal ofan effective antihistaminic or anti-anaphylactic amount of a chemicalcompound selected from the group consisting of1-{3-[4-(diphenylmethyl)-1-piperazinyl]propyl}-1H-benzimidazole and thepharmaceutically acceptable acid addition salts thereof.
 5. A method ofproducing antihistaminic or anti-anaphylactic activity in a warm-bloodedanimal in need of same which comprises systemic administration to saidwarm-blooded animal of an effective antihistaminic or anti-anaphylacticamount of a chemical compound selected from the group consisting of1-[4-{4-[(4-fluorophenyl)phenylmethyl]-1-piperazinyl}butyl]-1H-benzimidazoleand the pharmaceutically acceptable acid addition salts thereof.
 6. Amethod of producing antihistaminic or anti-anaphylactic activity in awarm-blooded animal in need of same which comprises systemicadministration to said warm-blooded animal of an effectiveantihistaminic or anti-anaphylactic amount of a chemical compoundselected from the group consisting of1-[4-{4-[bis(4-fluorophenyl)methyl]-1-piperazinyl}butyl]-1H-benzimidazoleand the pharmaceutically acceptable acid addition salts thereof.